Professore Associato SSD ING-IND 25 (DIFARMA)
+39.089.969240
Curriculum Accademico
L’Ing. Anna Angela Barba si e’ laureata con lode in Ingegneria Chimica, nel maggio 1997 e ha conseguito il titolo di dottore di ricerca in Ingegneria Chimica nel febbraio 2002. E’ stata borsista CNR nell’anno 1999 e post-doc nel biennio 2002-2004 e ha avuto incarichi di collaborazione coordinata e continuativa presso il Dipartimento di Ingegneria Chimica ed Alimentare dell’Universita’ degli Studi di Salerno (2004-2005).
Nel 2005 ha preso servizio nel ruolo di ricercatore presso il dipartimento di Scienze Farmaceutiche. Dal 2008 e’ ricercatore confermato presso il dipartimento di Scienze Farmaceutiche e Biomediche (gia’ Scienze Farmaceutiche).
Dall’anno accademico 2005-2006 all’anno accademico 2009-2010 e’ stata titolare dell’insegnamento di Impianti per l’Industria Farmaceutica per il corso di laurea specialistica in Farmacia. Ho svolto inoltre, nello stesso periodo, didattica integrativa per gli insegnamenti di Impianti Chimici e Impianti Chimici nell’Industria Farmaceutica per il corso di laurea specialistica in Chimica e Tecnologia Farmaceutica.
Ha svolto e svolge attivita’ didattica nei corsi di formazione post-laurea: Corso di Aggiornamento e Perfezionamento Professionale in Scienze dell’Alimentazione; Master Universitari di II livello in: Idrologia e Medicina Termale e dello Sport; Management Sanitario, Farmacoeconomia, Farmacovigilanza e aspetti gestionali; Scienza e Tecnologia Cosmetiche.
Fa parte del collegio di Dottorato in Ingegneria Chimica.
L’attivita’ di ricerca dell’Ing. Anna Angela Barba, svolta presso l’Universita’ degli Studi di Salerno, e’ stata sviluppata sulle applicazioni di potenza di campi elettromagnetici per lo sviluppo di metodologie e apparecchiature innovative per il riscaldamento assistito da microonde. Dall’ ottobre 2002 al marzo 2003 ha trascorso un periodo di ricerca presso l’Universita’ Tecnica di Eindhoven (NL) dove ha collaborato ad un progetto di ricerca interdipartimentale Department of Electrical Engineering / Department of Chemical Engineering and Chemistry, sul plasma pulsato.
Negli ultimi anni le attivita’ di ricerca svolte dall’Ing. Barba sono state improntate al trasferimento al settore farmaceutico e sanitario dei processi e dei metodi tipici dell’Ingegneria Chimica. Tali attivita’, svolte in collaborazioni scientifiche diverse e sia di carattere sperimentale che modellistico, sono state sviluppate in due diversi indirizzi aventi come comune denominatore, l’impiego di campi elettromagnetici, CEM (regione delle microonde). In particolare, sono state approfondite operazioni di riscaldamento di tipo intensificato (cottura, essiccamento, scottatura, curing) di matrici alimentari e di materiali ad uso farmaceutico; e sviluppate tecniche di indagini non convenzionali basate sulla misurazione delle proprieta’ dielettriche dei materiali (nanopolveri metalliche, materiali compositi, geli di biopolimeri).
L’ing. Anna Angela Barba e’ stata/è responsabile scientifico di progetti finanziati ed ha partecipato/ partecipa allo sviluppo di altri progetti finanziati. E’ autrice / co-autrice di molti lavori pubblicati su riviste internazionali, riviste nazionali a carattere tecnico, comunicazioni a convegni internazionali e nazionali, contributi in libri/monografie. E’ stata/ è revisore per numerose riviste internazionali.
Pubblicazioni
2022 |
De Piano, Raffaella ; Caccavo, Diego; Barba, Anna Angela; Lamberti, Gaetano Anionic hydrogels: equilibrium behaviour modelling Inproceedings CHISA - Prague (Czech Republic), 2022. BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @inproceedings{Piano}2022, title = {Anionic hydrogels: equilibrium behaviour modelling}, author = {Raffaella {De Piano} and Diego Caccavo and Anna Angela Barba and Gaetano Lamberti}, year = {2022}, date = {2022-08-23}, booktitle = {CHISA - Prague (Czech Republic)}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {inproceedings} } |
2018 |
Caccavo, Diego; Vietri, Antonella; Lamberti, Gaetano; Barba, Anna Angela; Larsson, Anette Modeling the mechanics and the transport phenomena in hydrogels Book Chapter Manca, Davide (Ed.): Quantitative Systems Pharmacology: Models and Model-Based Systems with Applications, Chapter 12, 2018. Abstract | Links | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @inbook{Caccavo2018b, title = {Modeling the mechanics and the transport phenomena in hydrogels}, author = {Diego Caccavo and Antonella Vietri and Gaetano Lamberti and Anna Angela Barba and Anette Larsson }, editor = {Davide Manca}, url = {https://www.sciencedirect.com/science/article/pii/B978044463964600012X}, doi = {10.1016/B978-0-444-63964-6.00012-X}, year = {2018}, date = {2018-07-18}, booktitle = {Quantitative Systems Pharmacology: Models and Model-Based Systems with Applications}, chapter = {12}, abstract = {Hydrogels are polymeric materials widely used in pharmaceutical and biomedical applications. Their uses can be improved by modeling their behavior, in particular the mechanical phenomena and the transport phenomena. The scope of this chapter is to propose a model, simple enough and with a limited number of parameters to be determined, able to capture the full behavior of a swelling hydrogel, with the aim of describing the drug release process as well as\textemdashin principle\textemdashany other application of hydrogels. The model was derived recalling the basics of the continuum mechanics, the possible approaches to estimate the Helmholtz free energy, and then writing the transport and constitutive equations for a poroelastic material, and for a more realistic poroviscoelastic material (by adding the standard linear solid model as the rheological model). A full extension to multicomponent systems, to describe the drug release phenomenon, is proposed along with a sensitivity analysis (free-swelling simulation by changing the model parameters).}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {inbook} } Hydrogels are polymeric materials widely used in pharmaceutical and biomedical applications. Their uses can be improved by modeling their behavior, in particular the mechanical phenomena and the transport phenomena. The scope of this chapter is to propose a model, simple enough and with a limited number of parameters to be determined, able to capture the full behavior of a swelling hydrogel, with the aim of describing the drug release process as well as—in principle—any other application of hydrogels. The model was derived recalling the basics of the continuum mechanics, the possible approaches to estimate the Helmholtz free energy, and then writing the transport and constitutive equations for a poroelastic material, and for a more realistic poroviscoelastic material (by adding the standard linear solid model as the rheological model). A full extension to multicomponent systems, to describe the drug release phenomenon, is proposed along with a sensitivity analysis (free-swelling simulation by changing the model parameters). |
Caccavo, Diego; Cascone, Sara; Lamberti, Gaetano; Barba, Anna Angela Hydrogels: experimental characterization and mathematical modelling of their mechanical and diffusive behaviour Journal Article Chemical Society Reviews, 47 (7), pp. 2357-2373, 2018, ISSN: 0306-0012. Abstract | Links | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @article{Caccavo2018, title = {Hydrogels: experimental characterization and mathematical modelling of their mechanical and diffusive behaviour}, author = {Diego Caccavo and Sara Cascone and Gaetano Lamberti and Anna Angela Barba}, url = {http://pubs.rsc.org/en/content/articlelanding/2018/cs/c7cs00638a#!divAbstract}, doi = {10.1039/C7CS00638A}, issn = {0306-0012}, year = {2018}, date = {2018-04-07}, journal = {Chemical Society Reviews}, volume = {47}, number = {7}, pages = {2357-2373}, abstract = {Hydrogels are materials widely used in countless applications, particularly in the biomedical, pharmaceutical, and nutraceutical fields, because of their biocompatibility and their mechanical and transport properties. Several approaches are known to evaluate their properties, but only a few approaches are under development to mathematically describe their behaviour, in terms of how the materials answer to mechanical stimuli and how incorporated active substances are released. In this review, the main properties of hydrogels are summarized and the structure\textendashproperty relationships are investigated (i.e. how the macromolecular structure influences the properties of macroscopic samples made of hydrogels). A selection criterion is proposed based on the comparison of three characteristic times: relaxation time, diffusion time, and process time. Then, the most common experimental methods to investigate the hydrogel properties are summarized, along with the state-of-the-art of mathematical modelling, with reference to the mechanical and transport properties of hydrogels, with particular attention to the viscoelastic and poroelastic behaviours. Last but not least, some case histories which can be classified as viscoelastic, poroelastic, or poroviscoelastic behaviours are presented.}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {article} } Hydrogels are materials widely used in countless applications, particularly in the biomedical, pharmaceutical, and nutraceutical fields, because of their biocompatibility and their mechanical and transport properties. Several approaches are known to evaluate their properties, but only a few approaches are under development to mathematically describe their behaviour, in terms of how the materials answer to mechanical stimuli and how incorporated active substances are released. In this review, the main properties of hydrogels are summarized and the structure–property relationships are investigated (i.e. how the macromolecular structure influences the properties of macroscopic samples made of hydrogels). A selection criterion is proposed based on the comparison of three characteristic times: relaxation time, diffusion time, and process time. Then, the most common experimental methods to investigate the hydrogel properties are summarized, along with the state-of-the-art of mathematical modelling, with reference to the mechanical and transport properties of hydrogels, with particular attention to the viscoelastic and poroelastic behaviours. Last but not least, some case histories which can be classified as viscoelastic, poroelastic, or poroviscoelastic behaviours are presented. |
2017 |
Caccavo, Diego; Barba, Anna Angela; D'Amore, Matteo; De Piano, Raffaella ; Lamberti, Gaetano; Rossi, Alessandra; Colombo, Paolo Modeling the modified drug release from curved shape drug delivery systems - Dome Matrix® Journal Article European Journal of Pharmaceutics and Biopharmaceutics, 121 , pp. 24-31, 2017, ISSN: 0939-6411. Abstract | Links | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @article{Caccavo2017b, title = {Modeling the modified drug release from curved shape drug delivery systems - Dome Matrix®}, author = {Diego Caccavo and Anna Angela Barba and Matteo D'Amore and Raffaella {De Piano} and Gaetano Lamberti and Alessandra Rossi and Paolo Colombo}, url = {http://www.sciencedirect.com/science/article/pii/S0939641117308366}, doi = {10.1016/j.ejpb.2017.08.016}, issn = {0939-6411}, year = {2017}, date = {2017-12-01}, journal = {European Journal of Pharmaceutics and Biopharmaceutics}, volume = {121}, pages = {24-31}, abstract = {The controlled drug release from hydrogel-based drug delivery systems is a topic of large interest for research in pharmacology. The mathematical modeling of the behavior of these systems is a tool of emerging relevance, since the simulations can be of use in the design of novel systems, in particular for complex shaped tablets. In this work a model, previously developed, was applied to complex-shaped oral drug delivery systems based on hydrogels (Dome Matrix®). Furthermore, the model was successfully adopted in the description of drug release from partially accessible Dome Matrix® systems (systems with some surfaces coated). In these simulations, the erosion rate was used as a fitting parameter, and its dependence upon the surface area/volume ratio and upon the local fluid dynamics was discussed. The model parameters were determined by comparison with the drug release profile from a cylindrical tablet, then the model was successfully used for the prediction of the drug release from a Dome Matrix® system, for simple module configuration and for module assembled (void and piled) configurations. It was also demonstrated that, given the same initial S/V ratio, the drug release is independent upon the shape of the tablets but it is only influenced by the S/V evolution. The model reveals itself able to describe the observed phenomena, and thus it can be of use for the design of oral drug delivery systems, even if complex shaped.}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {article} } The controlled drug release from hydrogel-based drug delivery systems is a topic of large interest for research in pharmacology. The mathematical modeling of the behavior of these systems is a tool of emerging relevance, since the simulations can be of use in the design of novel systems, in particular for complex shaped tablets. In this work a model, previously developed, was applied to complex-shaped oral drug delivery systems based on hydrogels (Dome Matrix®). Furthermore, the model was successfully adopted in the description of drug release from partially accessible Dome Matrix® systems (systems with some surfaces coated). In these simulations, the erosion rate was used as a fitting parameter, and its dependence upon the surface area/volume ratio and upon the local fluid dynamics was discussed. The model parameters were determined by comparison with the drug release profile from a cylindrical tablet, then the model was successfully used for the prediction of the drug release from a Dome Matrix® system, for simple module configuration and for module assembled (void and piled) configurations. It was also demonstrated that, given the same initial S/V ratio, the drug release is independent upon the shape of the tablets but it is only influenced by the S/V evolution. The model reveals itself able to describe the observed phenomena, and thus it can be of use for the design of oral drug delivery systems, even if complex shaped. |
Caccavo, Diego; Lamberti, Gaetano; Barba, Anna Angela; Abrahmsén-Alami, Susanna; Viridén, Anna; Larsson, Anette Effects of HPMC substituent pattern on water up-take, polymer and drug release: an experimental and modelling study Journal Article International Journal of Pharmaceutics, 528 (1-2), pp. 705-713, 2017, ISSN: 0378-5173. Abstract | Links | BibTeX | Tags: Erosion, HPMC, Hydrogel Characterization, Hydrogel Modeling, Mathematical modeling @article{Larsson2017, title = {Effects of HPMC substituent pattern on water up-take, polymer and drug release: an experimental and modelling study}, author = {Diego Caccavo and Gaetano Lamberti and Anna Angela Barba and Susanna Abrahms\'{e}n-Alami and Anna Virid\'{e}n and Anette Larsson}, url = {http://www.sciencedirect.com/science/article/pii/S0378517317305720}, doi = {10.1016/j.ijpharm.2017.06.064}, issn = {0378-5173}, year = {2017}, date = {2017-08-07}, journal = {International Journal of Pharmaceutics}, volume = {528}, number = {1-2}, pages = {705-713}, abstract = {The purpose of this study was to investigate the hydration behavior of two matrix formulations containing the cellulose derivative hydroxypropyl methylcellulose (HPMC). The two HPMC batches investigated had different substitution pattern along the backbone; the first one is referred to as heterogeneous and the second as homogenous. The release of both the drug molecule theophylline and the polymer was determined. Additionally, the water concentrations at different positions in the swollen gel layers were determined by Magnetic Resonance Imaging. The experimental data was compared to predicted values obtained by the extension of a mechanistic Fickian based model. The hydration of tablets containing the more homogenous HPMC batch showed a gradual water concentration gradient in the gel layer and could be well predicted. The hydration process for the more heterogeneous batch showed a very abrupt step change in the water concentration in the gel layer and could not be well predicted. Based on the comparison between the experimental and predicted data this study suggests, for the first time, that formulations with HPMC of different heterogeneities form gels in different ways. The homogeneous HPMC batch exhibits a water sorption behavior ascribable to a Fick´s law for the diffusion process whereas the more heterogeneous HPMC batches does not. This conclusion is important in the future development of simulation models and in the understanding of drug release mechanism from hydrophilic matrices. }, keywords = {Erosion, HPMC, Hydrogel Characterization, Hydrogel Modeling, Mathematical modeling}, pubstate = {published}, tppubtype = {article} } The purpose of this study was to investigate the hydration behavior of two matrix formulations containing the cellulose derivative hydroxypropyl methylcellulose (HPMC). The two HPMC batches investigated had different substitution pattern along the backbone; the first one is referred to as heterogeneous and the second as homogenous. The release of both the drug molecule theophylline and the polymer was determined. Additionally, the water concentrations at different positions in the swollen gel layers were determined by Magnetic Resonance Imaging. The experimental data was compared to predicted values obtained by the extension of a mechanistic Fickian based model. The hydration of tablets containing the more homogenous HPMC batch showed a gradual water concentration gradient in the gel layer and could be well predicted. The hydration process for the more heterogeneous batch showed a very abrupt step change in the water concentration in the gel layer and could not be well predicted. Based on the comparison between the experimental and predicted data this study suggests, for the first time, that formulations with HPMC of different heterogeneities form gels in different ways. The homogeneous HPMC batch exhibits a water sorption behavior ascribable to a Fick´s law for the diffusion process whereas the more heterogeneous HPMC batches does not. This conclusion is important in the future development of simulation models and in the understanding of drug release mechanism from hydrophilic matrices. |
Caccavo, Diego; Cascone, Sara; Lamberti, Gaetano; Dalmoro, Annalisa; Barba, Anna Angela Modeling of the behavior of natural polysaccharides hydrogels for bio-pharma applications Journal Article Natural Product Communications, 12 (6), pp. 867-871, 2017, ISSN: 1934-578X. Abstract | Links | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling, Hydrogels, Mathematical modeling, Modeling @article{NPC02, title = {Modeling of the behavior of natural polysaccharides hydrogels for bio-pharma applications}, author = {Diego Caccavo and Sara Cascone and Gaetano Lamberti and Annalisa Dalmoro and Anna Angela Barba}, url = {http://www.naturalproduct.us/index.asp https://www.gruppotpp.it/wp-content/uploads/2017/06/Caccavo-et-al-NPC-126-867-871-2017-Abstract.pdf}, issn = {1934-578X}, year = {2017}, date = {2017-07-31}, journal = {Natural Product Communications}, volume = {12}, number = {6}, pages = {867-871}, abstract = {Hydrogels, even if not exclusively obtained from natural sources, are widely used for pharmaceuticals and for biomedical applications. The reasons for their uses are their biocompatibility and the possibility to obtain systems and devices with different properties, due to variable characteristics of the materials. In order to effectively design and produce these systems and devices, two main ways are available: i) trial-and-error process, at least guided by experience, during which the composition of the system and the production steps are changed in order to get the desired behavior; ii) production process guided by the a-priori simulation of the systems’ behavior, thanks to proper tuned mathematical models of the reality. Of course the second approach, when applicable, allows tremendous savings in term of human and instrumental resources. In this mini-review, several modeling approaches useful to describe the behavior of natural polysaccharide-based hydrogels in bio-pharma applications are reported. In particular, reported case histories are: i) the size calculation of micro-particles obtained by ultrasound assisted atomization; ii) the release kinetics from core-shell micro-particles, iii) the solidification behavior of blends of synthetic and natural polymers for gel paving of blood vessels, iv) the drug release from hydrogel-based tablets. This material can be seen as a guide toward the use of mathematical modeling in bio-pharma applications. }, keywords = {Hydrogel Characterization, Hydrogel Modeling, Hydrogels, Mathematical modeling, Modeling}, pubstate = {published}, tppubtype = {article} } Hydrogels, even if not exclusively obtained from natural sources, are widely used for pharmaceuticals and for biomedical applications. The reasons for their uses are their biocompatibility and the possibility to obtain systems and devices with different properties, due to variable characteristics of the materials. In order to effectively design and produce these systems and devices, two main ways are available: i) trial-and-error process, at least guided by experience, during which the composition of the system and the production steps are changed in order to get the desired behavior; ii) production process guided by the a-priori simulation of the systems’ behavior, thanks to proper tuned mathematical models of the reality. Of course the second approach, when applicable, allows tremendous savings in term of human and instrumental resources. In this mini-review, several modeling approaches useful to describe the behavior of natural polysaccharide-based hydrogels in bio-pharma applications are reported. In particular, reported case histories are: i) the size calculation of micro-particles obtained by ultrasound assisted atomization; ii) the release kinetics from core-shell micro-particles, iii) the solidification behavior of blends of synthetic and natural polymers for gel paving of blood vessels, iv) the drug release from hydrogel-based tablets. This material can be seen as a guide toward the use of mathematical modeling in bio-pharma applications. |
Caccavo, Diego; Cascone, Sara; Poto, Serena; Lamberti, Gaetano; Barba, Anna Angela Mechanics and transport phenomena in agarose-based hydrogels studied by compression-relaxation tests Journal Article Carbohydrate Polymers, 167 , pp. 136–144, 2017. Abstract | Links | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @article{Caccavo2017b, title = {Mechanics and transport phenomena in agarose-based hydrogels studied by compression-relaxation tests}, author = {Diego Caccavo and Sara Cascone and Serena Poto and Gaetano Lamberti and Anna Angela Barba}, url = {http://www.sciencedirect.com/science/article/pii/S0144861717302837}, doi = {10.1016/j.carbpol.2017.03.027}, year = {2017}, date = {2017-07-01}, journal = {Carbohydrate Polymers}, volume = {167}, pages = {136\textendash144}, abstract = {Hydrogels are widespread materials, used in several frontier fields, due to their peculiar behavior: they couple solvent mass transport to system mechanics, exhibiting viscoelastic and poroelastic characteristics. The full understanding of this behavior is crucial to correctly design such complex systems. In this study agarose gels has been investigated through experimental stress-relaxation tests and with the aid of a 3D poroviscoelastic model. At the investigated experimental conditions, the agarose gels samples show a prevalent viscoelastic behavior, revealing limited water transport and an increase of the stiffness as well as of the relaxation time along with the polymer concentration. The model parameters, derived from the fitting of some experimental data, have been generalized and used to purely predict the behavior of another set of gels. The stress-relaxation tests coupled with mathematical modeling demonstrated to be a powerful tool to study hydrogels’ behavior. }, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {article} } Hydrogels are widespread materials, used in several frontier fields, due to their peculiar behavior: they couple solvent mass transport to system mechanics, exhibiting viscoelastic and poroelastic characteristics. The full understanding of this behavior is crucial to correctly design such complex systems. In this study agarose gels has been investigated through experimental stress-relaxation tests and with the aid of a 3D poroviscoelastic model. At the investigated experimental conditions, the agarose gels samples show a prevalent viscoelastic behavior, revealing limited water transport and an increase of the stiffness as well as of the relaxation time along with the polymer concentration. The model parameters, derived from the fitting of some experimental data, have been generalized and used to purely predict the behavior of another set of gels. The stress-relaxation tests coupled with mathematical modeling demonstrated to be a powerful tool to study hydrogels’ behavior. |
Kazlauske, Jurgita; Cafaro, Maria Margherita; Caccavo, Diego; Marucci, Maria Grazia; Lamberti, Gaetano; Barba, Anna Angela; Larsson, Anette Determination of the release mechanism of Theophylline from pellets coated with Surelease® − a water dispersion of Ethyl cellulose Journal Article International Journal of Pharmaceutics, 528 (1-2), pp. 345-353, 2017, ISSN: 0378-5173. Abstract | Links | BibTeX | Tags: Drug Delivery Systems, drug release, Hydrogel Characterization @article{Kazlauske2017, title = {Determination of the release mechanism of Theophylline from pellets coated with Surelease® − a water dispersion of Ethyl cellulose}, author = {Jurgita Kazlauske and Maria Margherita Cafaro and Diego Caccavo and Maria Grazia Marucci and Gaetano Lamberti and Anna Angela Barba and Anette Larsson}, url = {http://www.sciencedirect.com/science/article/pii/S0378517317304970}, doi = {10.1016/j.ijpharm.2017.05.073}, issn = {0378-5173}, year = {2017}, date = {2017-06-17}, journal = {International Journal of Pharmaceutics}, volume = {528}, number = {1-2}, pages = {345-353}, abstract = {The aim of this study was to investigate the water transport over free standing films based on the aqueous ethyl cellulose (EC) coating Surelease® and the drug (Theophylline) release mechanism from coated pellets. It was found that the main drug release rate from pellets was controlled by a diffusion mechanism. However, the drug release rate was altered by addition of sodium chloride to the external release medium. A decrease in the drug release rate when sodium chloride is added to the release medium has traditionally been used to indicate an osmotic drug release mechanism. However, our findings that the release rate decreased by sodium chloride addition could be explained by sodium chloride diffusing through the coating layer into the inner parts of the pellets, decreasing the solubility of Theophylline. This gave a reduced drug concentration gradient over the coating layer and thus a slower release rate. Furthermore, this study shows, as expected, that the transport of water through Surelease® films into the pellets was faster than the transport out of Theophylline (approx. seven times), which was the reason why the pellets were swelling during the release. It was also shown that the drug release rate, determined for both whole dose release and for single pellets, decreased with increasing thickness (from 16 to 51 μm) of the coating layer controlling the drug release rate.}, keywords = {Drug Delivery Systems, drug release, Hydrogel Characterization}, pubstate = {published}, tppubtype = {article} } The aim of this study was to investigate the water transport over free standing films based on the aqueous ethyl cellulose (EC) coating Surelease® and the drug (Theophylline) release mechanism from coated pellets. It was found that the main drug release rate from pellets was controlled by a diffusion mechanism. However, the drug release rate was altered by addition of sodium chloride to the external release medium. A decrease in the drug release rate when sodium chloride is added to the release medium has traditionally been used to indicate an osmotic drug release mechanism. However, our findings that the release rate decreased by sodium chloride addition could be explained by sodium chloride diffusing through the coating layer into the inner parts of the pellets, decreasing the solubility of Theophylline. This gave a reduced drug concentration gradient over the coating layer and thus a slower release rate. Furthermore, this study shows, as expected, that the transport of water through Surelease® films into the pellets was faster than the transport out of Theophylline (approx. seven times), which was the reason why the pellets were swelling during the release. It was also shown that the drug release rate, determined for both whole dose release and for single pellets, decreased with increasing thickness (from 16 to 51 μm) of the coating layer controlling the drug release rate. |
Caccavo, Diego; Lamberti, Gaetano; Cafaro, Maria Margherita; Barba, Anna Angela; Kazlauske, Jurgita; Larsson, Anette Mathematical modeling of the drug release from an ensemble of coated pellets Journal Article British Journal of Pharmacology, 174 (12), pp. 1797–1809 , 2017, ISBN: 1476-5381. Abstract | Links | BibTeX | Tags: Drug Delivery Systems, drug release, Hydrogel Characterization, Hydrogel Modeling @article{Caccavo2017b, title = {Mathematical modeling of the drug release from an ensemble of coated pellets}, author = {Diego Caccavo and Gaetano Lamberti and Maria Margherita Cafaro and Anna Angela Barba and Jurgita Kazlauske and Anette Larsson}, url = {http://onlinelibrary.wiley.com/doi/10.1111/bph.13776/abstract}, doi = {10.1111/bph.13776}, isbn = {1476-5381}, year = {2017}, date = {2017-04-22}, journal = {British Journal of Pharmacology}, volume = {174}, number = {12}, pages = {1797\textendash1809 }, abstract = {Background and Purpose Coated pellets are widely used as oral drug delivery systems, being highly accepted by patients and with several advantages with respect to single unit devices. The understanding of their behavior is therefore needed to improve the formulation effectiveness and to reduce the production costs. In spite of such an importance, not many mathematical modeling attempts have been made, mostly due to the complexities arising from the system polydispersity (non homogeneous multiple-unit particulate systems), which has been scarcely investigated with the aid of mechanistic models. Experimental approach In this work a mechanistic mathematical model able to describe the single pellet behavior in terms of hydration, drug dissolution, diffusion and release, and particle size change was developed. This model was then extended to describe and predict the behavior of mono- and poly-disperse ensembles of pellets. Key Results In particular the polydispersity arising from the inert core size distribution was proved to have a minimal effect on the drug release profile, whereas the size distribution of the polymeric film thickness showed to be the key parameter determining the drug release. Conclusions and Implications The developed mechanistic model, capable of considering the polydispersity of the system, was able to predict the release kinetics from ensembles of pellets and to highlight the key parameters to control in the production of pellets-based drug delivery systems, demonstrating its use as a powerful predictive tool.}, keywords = {Drug Delivery Systems, drug release, Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {article} } Background and Purpose Coated pellets are widely used as oral drug delivery systems, being highly accepted by patients and with several advantages with respect to single unit devices. The understanding of their behavior is therefore needed to improve the formulation effectiveness and to reduce the production costs. In spite of such an importance, not many mathematical modeling attempts have been made, mostly due to the complexities arising from the system polydispersity (non homogeneous multiple-unit particulate systems), which has been scarcely investigated with the aid of mechanistic models. Experimental approach In this work a mechanistic mathematical model able to describe the single pellet behavior in terms of hydration, drug dissolution, diffusion and release, and particle size change was developed. This model was then extended to describe and predict the behavior of mono- and poly-disperse ensembles of pellets. Key Results In particular the polydispersity arising from the inert core size distribution was proved to have a minimal effect on the drug release profile, whereas the size distribution of the polymeric film thickness showed to be the key parameter determining the drug release. Conclusions and Implications The developed mechanistic model, capable of considering the polydispersity of the system, was able to predict the release kinetics from ensembles of pellets and to highlight the key parameters to control in the production of pellets-based drug delivery systems, demonstrating its use as a powerful predictive tool. |
Dalmoro, Annalisa; Abrami, Michela; Galzerano, Barbara; Bochicchio, Sabrina; Barba, Anna Angela; Grassi, Mario; Larobina, Domenico Injectable chitosan/b-glycerophosphate system for sustained release: gelation study, structural investigation and erosion tests Journal Article Current Drug Delivery, 14 (2), pp. 216 - 223, 2017. Abstract | Links | BibTeX | Tags: Hydrogel Characterization @article{Dalmoro2016b, title = { Injectable chitosan/b-glycerophosphate system for sustained release: gelation study, structural investigation and erosion tests}, author = {Annalisa Dalmoro and Michela Abrami and Barbara Galzerano and Sabrina Bochicchio and Anna Angela Barba and Mario Grassi and Domenico Larobina}, url = {https://www.gruppotpp.it/wp-content/uploads/2017/03/06.-Dalmoro-et-al-CDD-142-216-223-2017.pdf http://benthamscience.com/journals/current-drug-delivery/volume/14/issue/2/page/216/ }, doi = {10.2174/1567201813666160721142202}, year = {2017}, date = {2017-02-08}, issuetitle = {NEW TRENDS IN GENE THERAPY: MULTIDISCIPLINARY APPROACHES TO SIRNAS CONTROLLED DELIVERY}, journal = {Current Drug Delivery}, volume = {14}, number = {2}, pages = {216 - 223}, abstract = {Hydrogels can constitute reliable delivery systems of drugs, including those based on nucleic acids (NABDs) such as small interfering ribonucleic acid (siRNA). Their nature, structure, and response to physiological or external stimuli strongly influence the delivery mechanisms of entrapped active molecules, and, in turns, their possible uses in pharmacological and biomedical applications. In this study a thermo-gelling chitosan/β-glycero-phosphate system has been optimized in order to assess its use as injectable system able to: i) gelling at physiological pH and temperature, and ii) modulate the release of included active ingredients. To this aim we first analyzed the effect of acetic acid concentration on the gelation temperature. We then found the “optimized composition”, namely, the one in which the Tgel is equal to the physiological temperature. The resulting gel was tested, by low field nuclear magnetic resonance (LF-NMR), to evaluate its average mesh-size, which can affect release kinetics of loaded drug. Finally, films of gelled chitosan, loaded with a model drug, have been tested in vitro to monitor their characteristic times, i.e. diffusion and erosion time, when they are exposed to a medium mimicking a physiological environment (buffer solution at pH 7.4). Results display that the optimized system is deemed to be an ideal candidate as injectable gelling material for a sustained release.}, keywords = {Hydrogel Characterization}, pubstate = {published}, tppubtype = {article} } Hydrogels can constitute reliable delivery systems of drugs, including those based on nucleic acids (NABDs) such as small interfering ribonucleic acid (siRNA). Their nature, structure, and response to physiological or external stimuli strongly influence the delivery mechanisms of entrapped active molecules, and, in turns, their possible uses in pharmacological and biomedical applications. In this study a thermo-gelling chitosan/β-glycero-phosphate system has been optimized in order to assess its use as injectable system able to: i) gelling at physiological pH and temperature, and ii) modulate the release of included active ingredients. To this aim we first analyzed the effect of acetic acid concentration on the gelation temperature. We then found the “optimized composition”, namely, the one in which the Tgel is equal to the physiological temperature. The resulting gel was tested, by low field nuclear magnetic resonance (LF-NMR), to evaluate its average mesh-size, which can affect release kinetics of loaded drug. Finally, films of gelled chitosan, loaded with a model drug, have been tested in vitro to monitor their characteristic times, i.e. diffusion and erosion time, when they are exposed to a medium mimicking a physiological environment (buffer solution at pH 7.4). Results display that the optimized system is deemed to be an ideal candidate as injectable gelling material for a sustained release. |
2016 |
Lamberti, Gaetano; Barba, Anna Angela; Cascone, Sara; Dalmoro, Annalisa; Caccavo, Diego An Engineering Point of View on the Use of the Hydrogels for Pharmaceutical and Biomedical Applications Book Chapter Majee, Sutapa Biswas (Ed.): Emerging Concepts in Analysis and Applications of Hydrogels, Chapter 8, Intech, 2016, ISBN: 978-953-51-2510-5. Abstract | Links | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @inbook{Lamberti2016b, title = {An Engineering Point of View on the Use of the Hydrogels for Pharmaceutical and Biomedical Applications}, author = {Gaetano Lamberti and Anna Angela Barba and Sara Cascone and Annalisa Dalmoro and Diego Caccavo}, editor = {Sutapa Biswas Majee}, url = {http://www.intechopen.com/books/emerging-concepts-in-analysis-and-applications-of-hydrogels/an-engineering-point-of-view-on-the-use-of-the-hydrogels-for-pharmaceutical-and-biomedical-applicati}, doi = {10.5772/64299 }, isbn = {978-953-51-2510-5}, year = {2016}, date = {2016-08-24}, booktitle = {Emerging Concepts in Analysis and Applications of Hydrogels}, publisher = {Intech}, chapter = {8}, abstract = {In this chapter, the modern uses of hydrogels in pharmaceutical and biomedical applications are revised following an engineering point of view, i.e. focusing the attention on material properties and process conditions. The chapter discusses the applications following the increase in scale‐size. First, the nanoscale systems, i.e. hydrogel nanoparticles (HNPs), are analysed in terms of preparative approaches (polymerization methods and uses of preformed polymers) and with a brief mention of the future trends in the field. Secondly, systems based on hydrogel microparticles (HMPs) are examined following the same scheme (polymerization methods, uses of preformed polymers, a mention of novel and future trends). Thirdly, and last but not the least, the hydrogel‐based drug delivery systems (macroscopic HB‐DDSs) are presented, focusing in particular on tablets made of hydrogels, discussing the characterization methods and on the modelling approaches used to describe their behaviour. Other macroscopic systems are also discussed in brief. Even if the vastness of the field makes its discussion impossible in a single chapter, the presented material can be a good starting point to study the uses of hydrogels in pharmaceutical and biomedical sciences.}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {inbook} } In this chapter, the modern uses of hydrogels in pharmaceutical and biomedical applications are revised following an engineering point of view, i.e. focusing the attention on material properties and process conditions. The chapter discusses the applications following the increase in scale‐size. First, the nanoscale systems, i.e. hydrogel nanoparticles (HNPs), are analysed in terms of preparative approaches (polymerization methods and uses of preformed polymers) and with a brief mention of the future trends in the field. Secondly, systems based on hydrogel microparticles (HMPs) are examined following the same scheme (polymerization methods, uses of preformed polymers, a mention of novel and future trends). Thirdly, and last but not the least, the hydrogel‐based drug delivery systems (macroscopic HB‐DDSs) are presented, focusing in particular on tablets made of hydrogels, discussing the characterization methods and on the modelling approaches used to describe their behaviour. Other macroscopic systems are also discussed in brief. Even if the vastness of the field makes its discussion impossible in a single chapter, the presented material can be a good starting point to study the uses of hydrogels in pharmaceutical and biomedical sciences. |
Caccavo, Diego; Cascone, Sara; Lamberti, Gaetano; Barba, Anna Angela; Larsson, Anette Swellable Hydrogel-based Systems for Controlled Drug Delivery Book Chapter Sezer, Ali Demir (Ed.): Smart Drug Delivery System, Chapter 10, Intech, 2016, ISBN: 978-953-51-2247-0. Abstract | Links | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @inbook{Caccavo2016b, title = {Swellable Hydrogel-based Systems for Controlled Drug Delivery}, author = {Diego Caccavo and Sara Cascone and Gaetano Lamberti and Anna Angela Barba and Anette Larsson}, editor = {Ali Demir Sezer}, url = {http://www.intechopen.com/books/smart-drug-delivery-system/swellable-hydrogel-based-systems-for-controlled-drug-delivery#exportas}, doi = {10.5772/61792}, isbn = {978-953-51-2247-0}, year = {2016}, date = {2016-02-10}, booktitle = {Smart Drug Delivery System}, publisher = {Intech}, chapter = {10}, abstract = {The controlled delivery of drugs can be effectively obtained using systems based on hydrogels. Tablets, to be orally administered, represent the simplest and the most traditional dosage systems based on hydrogel. Their formulation and preparation require to mix and to compress, in proper ratios, various excipients, including a swellable polymer and a drug. Carriers for controlled release systems are usually cross-linked polymers able to form hydrogels that show peculiar release mechanisms, where both diffusion and tablet swelling play important roles.When a dry swellable hydrogel-based matrix is immersed in a physiological fluid, this starts to penetrate inside the polymeric hydrophilic matrix. When a certain solvent concentration is reached, the polymeric chains unfold due to a glass\textendashrubber transition, and a gel-like layer is formed. In the swollen region, the drug molecules can easily diffuse toward the outer dissolution medium, once they are dissolved. The polymer network became extremely hydrated where the swollen matrix is in contact with the outer medium, and processes like chain disentanglement take place, “eroding” the matrix.This chapter is focused on the analysis of the state of the art about the uses of carriers for controlled release systems composed by hydrogel-based matrices. This analysis has been performed studying in deep both the experimental and the modeling techniques which have been investigated over the years to characterize all the phenomena involved during the drug release.}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {inbook} } The controlled delivery of drugs can be effectively obtained using systems based on hydrogels. Tablets, to be orally administered, represent the simplest and the most traditional dosage systems based on hydrogel. Their formulation and preparation require to mix and to compress, in proper ratios, various excipients, including a swellable polymer and a drug. Carriers for controlled release systems are usually cross-linked polymers able to form hydrogels that show peculiar release mechanisms, where both diffusion and tablet swelling play important roles.When a dry swellable hydrogel-based matrix is immersed in a physiological fluid, this starts to penetrate inside the polymeric hydrophilic matrix. When a certain solvent concentration is reached, the polymeric chains unfold due to a glass–rubber transition, and a gel-like layer is formed. In the swollen region, the drug molecules can easily diffuse toward the outer dissolution medium, once they are dissolved. The polymer network became extremely hydrated where the swollen matrix is in contact with the outer medium, and processes like chain disentanglement take place, “eroding” the matrix.This chapter is focused on the analysis of the state of the art about the uses of carriers for controlled release systems composed by hydrogel-based matrices. This analysis has been performed studying in deep both the experimental and the modeling techniques which have been investigated over the years to characterize all the phenomena involved during the drug release. |
2015 |
Caccavo, Diego; Lamberti, Gaetano; Cascone, Sara; Barba, Anna Angela; Larsson, Anette Understanding the adhesion phenomena in carbohydrate-hydrogel-based systems: Water up-take, swelling and elastic detachment Journal Article Carbohydrate Polymers, 131 , pp. 41–49, 2015, ISSN: 01448617. Abstract | Links | BibTeX | Tags: Bio-adhesion, Carbopol, Elastic behavior, Hydrogel Characterization, Hydrogel Modeling, Modeling, Water transport @article{Caccavo2015b, title = {Understanding the adhesion phenomena in carbohydrate-hydrogel-based systems: Water up-take, swelling and elastic detachment}, author = { Diego Caccavo and Gaetano Lamberti and Sara Cascone and Anna Angela Barba and Anette Larsson}, url = {http://www.sciencedirect.com/science/article/pii/S0144861715004476}, doi = {10.1016/j.carbpol.2015.05.041}, issn = {01448617}, year = {2015}, date = {2015-10-01}, journal = {Carbohydrate Polymers}, volume = {131}, pages = {41--49}, abstract = {The bio-adhesion is a complex phenomenon which takes place when two materials (at least one of biological nature, the other usually is a polymeric one) are held together for extended periods of time, usually for local drug delivery purposes. Despite bio-adhesion is widely exploited in commercial pharmaceuticals such as the buccal patches, the underlying phenomena of the process are not completely clarified yet. In this study experimental tests, in which the role of biological membranes is played by a water-rich agarose gel whereas patches are mimicked by hydrogel tablets (made of Carbopol or of Carbopol added with NaCl), have been used to analyze the behavior of the model system above described. Tablets have been forced to adhere on the agarose gel, and after a given contact time they have been detached, recording the required forces. Furthermore weight gain of the tablets (the water transported from the agarose gel toward the tablet) has been quantified. Water transport (during the time in which the contact between tablet and agarose gel is held) and elastic part of mechanical response during the detachment are modelled to achieve a better understanding of the adhesion process. Both the two sub-models nicely reproduce, respectively, the weight gain as well as the swelling of the Carbopol tablets, and the point at which the mechanical response ceases to be purely elastic.}, keywords = {Bio-adhesion, Carbopol, Elastic behavior, Hydrogel Characterization, Hydrogel Modeling, Modeling, Water transport}, pubstate = {published}, tppubtype = {article} } The bio-adhesion is a complex phenomenon which takes place when two materials (at least one of biological nature, the other usually is a polymeric one) are held together for extended periods of time, usually for local drug delivery purposes. Despite bio-adhesion is widely exploited in commercial pharmaceuticals such as the buccal patches, the underlying phenomena of the process are not completely clarified yet. In this study experimental tests, in which the role of biological membranes is played by a water-rich agarose gel whereas patches are mimicked by hydrogel tablets (made of Carbopol or of Carbopol added with NaCl), have been used to analyze the behavior of the model system above described. Tablets have been forced to adhere on the agarose gel, and after a given contact time they have been detached, recording the required forces. Furthermore weight gain of the tablets (the water transported from the agarose gel toward the tablet) has been quantified. Water transport (during the time in which the contact between tablet and agarose gel is held) and elastic part of mechanical response during the detachment are modelled to achieve a better understanding of the adhesion process. Both the two sub-models nicely reproduce, respectively, the weight gain as well as the swelling of the Carbopol tablets, and the point at which the mechanical response ceases to be purely elastic. |
Abrahmsén-Alami, Susanna; Caccavo, Diego; Lamberti, Gaetano; Barba, Anna Angela; Viridén, Anna; Larsson, Anette Hydrogel-based drug delivery systems (HB-DDSs): a combined experimental-modeling approach Journal Article AstraZeneca Internal Journal, pp. 1-2, 2015. Abstract | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @article{Abrahms\'{e}n-Alami2015, title = {Hydrogel-based drug delivery systems (HB-DDSs): a combined experimental-modeling approach}, author = {Susanna Abrahms\'{e}n-Alami and Diego Caccavo and Gaetano Lamberti and Anna Angela Barba and Anna Virid\'{e}n and Anette Larsson}, year = {2015}, date = {2015-09-01}, journal = {AstraZeneca Internal Journal}, pages = {1-2}, abstract = {In this work, a method based on MR image analysis, already used to quantify the water content in hydrating tablets based on hydrogels, was refined and it was proved to be a powerful source of detailed information: the water contents were obtained as function of position and time for commercial-like tablets based on HPMC, along with the tablets’ shape changes with time, and the drug release kinetics. A mechanistic model, based on transient mass balances and surface deformation due to the hydration and erosion, previously developed and tuned, was thus applied to describe the observed phenomena, giving good results. Both the experimental technique and the mechanistic model have confirmed to be useful tools for the study of the behavior \textendash as well as for the design \textendash of the tablets based on hydrogels.}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {article} } In this work, a method based on MR image analysis, already used to quantify the water content in hydrating tablets based on hydrogels, was refined and it was proved to be a powerful source of detailed information: the water contents were obtained as function of position and time for commercial-like tablets based on HPMC, along with the tablets’ shape changes with time, and the drug release kinetics. A mechanistic model, based on transient mass balances and surface deformation due to the hydration and erosion, previously developed and tuned, was thus applied to describe the observed phenomena, giving good results. Both the experimental technique and the mechanistic model have confirmed to be useful tools for the study of the behavior – as well as for the design – of the tablets based on hydrogels. |
Caccavo, Diego; Apicella, Pietro; Cascone, Sara; Dalmoro, Annalisa; Lamberti, Gaetano; Barba, Anna Angela Hydrogels-based systems for controlled release in agricultural applications Inproceedings 42nd Annual Meeting & Exposition of the Controlled Release Society, 2015. BibTeX | Tags: Hydrogel Characterization @inproceedings{Caccavo2015b, title = {Hydrogels-based systems for controlled release in agricultural applications}, author = {Diego Caccavo and Pietro Apicella and Sara Cascone and Annalisa Dalmoro and Gaetano Lamberti and Anna Angela Barba }, year = {2015}, date = {2015-07-26}, booktitle = {42nd Annual Meeting & Exposition of the Controlled Release Society}, keywords = {Hydrogel Characterization}, pubstate = {published}, tppubtype = {inproceedings} } |
Caccavo, Diego; Cascone, Sara; Lamberti, Gaetano; Barba, Anna Angela Hydrogel-Based CRSs Analyses: Testing And Modeling Inproceedings 1st International Congress of Controlled Release Society - Greek Local Chapter, pp. 1–1, 1st International Congress of Controlled Release Society, Athens (Greece), 2015. BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @inproceedings{caccavo2015b, title = {Hydrogel-Based CRSs Analyses: Testing And Modeling}, author = { Diego Caccavo and Sara Cascone and Gaetano Lamberti and Anna Angela Barba}, year = {2015}, date = {2015-05-01}, booktitle = {1st International Congress of Controlled Release Society - Greek Local Chapter}, pages = {1--1}, publisher = {1st International Congress of Controlled Release Society}, address = {Athens (Greece)}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {inproceedings} } |
Caccavo, Diego; Cascone, Sara; Lamberti, Gaetano; Barba, Anna Angela Controlled drug release from hydrogel-based matrices: Experiments and modeling. Journal Article International journal of pharmaceutics, 486 (1-2), pp. 144–152, 2015, ISSN: 1873-3476. Abstract | Links | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling, Hydrogels, Modeling, Texture analysis, Transport phenomena, Water uptake @article{Caccavo2015a, title = {Controlled drug release from hydrogel-based matrices: Experiments and modeling.}, author = { Diego Caccavo and Sara Cascone and Gaetano Lamberti and Anna Angela Barba}, url = {http://www.sciencedirect.com/science/article/pii/S0378517315002707}, doi = {10.1016/j.ijpharm.2015.03.054}, issn = {1873-3476}, year = {2015}, date = {2015-03-01}, journal = {International journal of pharmaceutics}, volume = {486}, number = {1-2}, pages = {144--152}, abstract = {Controlled release by oral administration is mainly achieved by pharmaceuticals based on hydrogels. Once swallowed, a matrix made of hydrogels experiences water up-take, swelling, drug dissolution and diffusion, polymer erosion. The detailed understanding and quantification of such a complex behavior is a mandatory prerequisite to the design of novel pharmaceuticals for controlled oral delivery. In this work, the behavior of hydrogel-based matrices has been investigated by means of several experimental techniques previously pointed out (gravimetric, and based on texture analysis); and then all the observed features were mathematically described using a physical model, defined and recently improved by our research group (based on balance equations, rate equations and swelling predictions). The agreement between the huge set of experimental data and the detailed calculations by the model is good, confirming the validity of both the experimental and the theoretical approaches.}, keywords = {Hydrogel Characterization, Hydrogel Modeling, Hydrogels, Modeling, Texture analysis, Transport phenomena, Water uptake}, pubstate = {published}, tppubtype = {article} } Controlled release by oral administration is mainly achieved by pharmaceuticals based on hydrogels. Once swallowed, a matrix made of hydrogels experiences water up-take, swelling, drug dissolution and diffusion, polymer erosion. The detailed understanding and quantification of such a complex behavior is a mandatory prerequisite to the design of novel pharmaceuticals for controlled oral delivery. In this work, the behavior of hydrogel-based matrices has been investigated by means of several experimental techniques previously pointed out (gravimetric, and based on texture analysis); and then all the observed features were mathematically described using a physical model, defined and recently improved by our research group (based on balance equations, rate equations and swelling predictions). The agreement between the huge set of experimental data and the detailed calculations by the model is good, confirming the validity of both the experimental and the theoretical approaches. |
Caccavo, Diego; Cascone, Sara; Amoroso, Maria Chiara; Apicella, Pietro; Lamberti, Gaetano; Barba, Anna Angela Hydrogel-based Granular Phytostrengtheners for Prolonged Release: Production and Characterization Journal Article Chemical Engineering Transaction, 44 , pp. 235–240, 2015. Abstract | Links | BibTeX | Tags: Granulation, Hydrogel Characterization, Tecnagri @article{Caccavo2015, title = {Hydrogel-based Granular Phytostrengtheners for Prolonged Release: Production and Characterization}, author = { Diego Caccavo and Sara Cascone and Maria Chiara Amoroso and Pietro Apicella and Gaetano Lamberti and Anna Angela Barba}, url = {http://www.aidic.it/cet/15/44/040.pdf}, doi = {10.3303/CET1544040}, year = {2015}, date = {2015-01-01}, journal = {Chemical Engineering Transaction}, volume = {44}, pages = {235--240}, abstract = {Soil wellness is an indispensable requirement to obtain fruits and vegetables with finest quality and with high yields. To the purpose, periodical administrations of nutrients, as well as phytostrengtheners could be required. Crucial goals to maximize the economic and environmental sustainability of the whole cultivation are the decrease of the dosages number together with the increase of the active substance availability within the soil. With these aims a controlled release phytostrengtheners encapsulated in a granular Hydroxypropyl methylcellulose matrix has been developed exploiting the wet granulation process. The granular product has been analyzed in terms of Particle Size Distribution (PSD), morphology and flowability. The results showed the effectiveness of the granulation process and the good flowability of the granules, highly desirable features for the product handling and commercialization.}, keywords = {Granulation, Hydrogel Characterization, Tecnagri}, pubstate = {published}, tppubtype = {article} } Soil wellness is an indispensable requirement to obtain fruits and vegetables with finest quality and with high yields. To the purpose, periodical administrations of nutrients, as well as phytostrengtheners could be required. Crucial goals to maximize the economic and environmental sustainability of the whole cultivation are the decrease of the dosages number together with the increase of the active substance availability within the soil. With these aims a controlled release phytostrengtheners encapsulated in a granular Hydroxypropyl methylcellulose matrix has been developed exploiting the wet granulation process. The granular product has been analyzed in terms of Particle Size Distribution (PSD), morphology and flowability. The results showed the effectiveness of the granulation process and the good flowability of the granules, highly desirable features for the product handling and commercialization. |
2014 |
Caccavo, Diego; Cascone, Sara; Lamberti, Gaetano; Barba, Anna Angela Testing and modelling of hydrogels behavior for pharmaceutical and biomedical applications Inproceedings Proceedings of CHISA 2014, pp. 1–1, CHISA 2014, Prague, Czech Republic, 2014. BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @inproceedings{d.2014, title = {Testing and modelling of hydrogels behavior for pharmaceutical and biomedical applications}, author = { Diego Caccavo and Sara Cascone and Gaetano Lamberti and Anna Angela Barba}, year = {2014}, date = {2014-08-01}, booktitle = {Proceedings of CHISA 2014}, pages = {1--1}, publisher = {CHISA 2014}, address = {Prague, Czech Republic}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {inproceedings} } |
Cascone, Sara; Lamberti, Gaetano; Titomanlio, Giuseppe; D'Amore, Matteo; Barba, Anna Angela Measurements of non-uniform water content in hydroxypropyl-methyl-cellulose based matrices via texture analysis Journal Article Carbohydrate Polymers, 103 , pp. 348–354, 2014, ISSN: 01448617. Abstract | Links | BibTeX | Tags: Hydrogel Characterization, Hydrogels, Texture analysis, Water content @article{Cascone2014, title = {Measurements of non-uniform water content in hydroxypropyl-methyl-cellulose based matrices via texture analysis}, author = { Sara Cascone and Gaetano Lamberti and Giuseppe Titomanlio and Matteo D'Amore and Anna Angela Barba}, url = {http://www.sciencedirect.com/science/article/pii/S0144861713012757}, doi = {10.1016/j.carbpol.2013.12.060}, issn = {01448617}, year = {2014}, date = {2014-03-01}, journal = {Carbohydrate Polymers}, volume = {103}, pages = {348--354}, abstract = {The use of hydrogels in the preparation of controlled release pharmaceutical forms is extensively diffused. The main feature of these polymers is their ability to swell forming a gel layer when they enter in contact with fluids. Once the gel layer is formed, the drug contained in the matrix can easily diffuse ensuring a controlled release from the tablet. Measurement of water content within a hydrating matrix based on hydrogels is a key topic in the study of pharmaceutical solid dosage forms. The aim of this work is to evaluate the water content of swollen matrices composed by HPMC and theophylline both in axial and in radial direction, as a function of time, using a texture analysis. A relationship between water content and slope of the force\textendashpenetration curves has been obtained using a simplified system in which the water uptake is allowed only in radial direction, obtaining thus partially hydrated matrices with the water content varying only along the radial direction. Once the relationship has been validated, it has been applied in a more complex system in which the polymer swelling takes place in both axial and radial direction. Thus, using the texture analysis it has been possible to determine the water in each position within the hydrated matrices.}, keywords = {Hydrogel Characterization, Hydrogels, Texture analysis, Water content}, pubstate = {published}, tppubtype = {article} } The use of hydrogels in the preparation of controlled release pharmaceutical forms is extensively diffused. The main feature of these polymers is their ability to swell forming a gel layer when they enter in contact with fluids. Once the gel layer is formed, the drug contained in the matrix can easily diffuse ensuring a controlled release from the tablet. Measurement of water content within a hydrating matrix based on hydrogels is a key topic in the study of pharmaceutical solid dosage forms. The aim of this work is to evaluate the water content of swollen matrices composed by HPMC and theophylline both in axial and in radial direction, as a function of time, using a texture analysis. A relationship between water content and slope of the force–penetration curves has been obtained using a simplified system in which the water uptake is allowed only in radial direction, obtaining thus partially hydrated matrices with the water content varying only along the radial direction. Once the relationship has been validated, it has been applied in a more complex system in which the polymer swelling takes place in both axial and radial direction. Thus, using the texture analysis it has been possible to determine the water in each position within the hydrated matrices. |
2013 |
Lamberti, Gaetano; Cascone, Sara; Cafaro, Maria Margherita; Titomanlio, Giuseppe; D'Amore, Matteo; Barba, Anna Angela Measurements of water content in hydroxypropyl-methyl-cellulose based hydrogels via texture analysis. Journal Article Carbohydrate polymers, 92 (1), pp. 765–8, 2013, ISSN: 1879-1344. Abstract | Links | BibTeX | Tags: HPMC, Hydrogel Characterization, Texture analysis, Water content @article{Lamberti2013a, title = {Measurements of water content in hydroxypropyl-methyl-cellulose based hydrogels via texture analysis.}, author = { Gaetano Lamberti and Sara Cascone and Maria Margherita Cafaro and Giuseppe Titomanlio and Matteo D'Amore and Anna Angela Barba}, url = {http://www.sciencedirect.com/science/article/pii/S0144861712010193}, doi = {10.1016/j.carbpol.2012.10.003}, issn = {1879-1344}, year = {2013}, date = {2013-01-01}, journal = {Carbohydrate polymers}, volume = {92}, number = {1}, pages = {765--8}, abstract = {In this work, a fast and accurate method to evaluate the water content in a cellulose derivative-based matrix subjected to controlled hydration was proposed and tuned. The method is based on the evaluation of the work of penetration required in the needle compression test. The work of penetration was successfully related to the hydrogel water content, assayed by a gravimetric technique. Moreover, a fitting model was proposed to correlate the two variables (the water content and the work of penetration). The availability of a reliable tool is useful both in the quantification of the water uptake phenomena, both in the management of the testing processes of novel pharmaceutical solid dosage forms.}, keywords = {HPMC, Hydrogel Characterization, Texture analysis, Water content}, pubstate = {published}, tppubtype = {article} } In this work, a fast and accurate method to evaluate the water content in a cellulose derivative-based matrix subjected to controlled hydration was proposed and tuned. The method is based on the evaluation of the work of penetration required in the needle compression test. The work of penetration was successfully related to the hydrogel water content, assayed by a gravimetric technique. Moreover, a fitting model was proposed to correlate the two variables (the water content and the work of penetration). The availability of a reliable tool is useful both in the quantification of the water uptake phenomena, both in the management of the testing processes of novel pharmaceutical solid dosage forms. |
2012 |
Dalmoro, Annalisa; Barba, Anna Angela; Lamberti, Gaetano; Grassi, Mario; D'Amore, Matteo Pharmaceutical applications of biocompatible polymer blends containing sodium alginate Journal Article Advances in Polymer Technology, 31 (3), pp. 219–230, 2012, ISSN: 07306679. Abstract | Links | BibTeX | Tags: Alginate gel film, Alginate shell{–}core particles, Biocompatibility, Crosslinking, Hydrogel Characterization, Hydrogels, Micro and Nano Vectors @article{Dalmoro2012a, title = {Pharmaceutical applications of biocompatible polymer blends containing sodium alginate}, author = { Annalisa Dalmoro and Anna Angela Barba and Gaetano Lamberti and Mario Grassi and Matteo D'Amore}, url = {http://doi.wiley.com/10.1002/adv.21276}, doi = {10.1002/adv.21276}, issn = {07306679}, year = {2012}, date = {2012-09-01}, journal = {Advances in Polymer Technology}, volume = {31}, number = {3}, pages = {219--230}, publisher = {Wiley Subscription Services, Inc., A Wiley Company}, abstract = {Biocompatible polymer blends, such as alginate blends, have a widespread use in pharmaceutical and medical applications due to their specific features, such as biodegradation, adhesiveness, and thermo- and pH sensitivity and that can be obtained from the mixture composition. In this work, the use of alginate blends was tested in a novel production methodology of therapeutic dosage forms based on polymeric chain reticulation phenomena induced by exposure to bivalent ions. Two kinds of sodium alginate were used to obtain gel films (structured films) in blends with Pluronic F127®. The blends were considered for applications in gel paving of drug-eluting stents. Sodium alginate was also used in shell\textendashcore particle production (structured particles) to obtain shell-barrier reducing drug release in the preparative steps (see wash operations). Both structures, films and particles, were obtained using Cu2+ and Ca2+ ions, respectively. Film/shell barrier properties were tested in dissolution experiments using vitamin B12 as an active molecule model. Experimental work demonstrated that the alginate composition is a crucial point in defining reticulated structures.}, keywords = {Alginate gel film, Alginate shell{\textendash}core particles, Biocompatibility, Crosslinking, Hydrogel Characterization, Hydrogels, Micro and Nano Vectors}, pubstate = {published}, tppubtype = {article} } Biocompatible polymer blends, such as alginate blends, have a widespread use in pharmaceutical and medical applications due to their specific features, such as biodegradation, adhesiveness, and thermo- and pH sensitivity and that can be obtained from the mixture composition. In this work, the use of alginate blends was tested in a novel production methodology of therapeutic dosage forms based on polymeric chain reticulation phenomena induced by exposure to bivalent ions. Two kinds of sodium alginate were used to obtain gel films (structured films) in blends with Pluronic F127®. The blends were considered for applications in gel paving of drug-eluting stents. Sodium alginate was also used in shell–core particle production (structured particles) to obtain shell-barrier reducing drug release in the preparative steps (see wash operations). Both structures, films and particles, were obtained using Cu2+ and Ca2+ ions, respectively. Film/shell barrier properties were tested in dissolution experiments using vitamin B12 as an active molecule model. Experimental work demonstrated that the alginate composition is a crucial point in defining reticulated structures. |
Lamberti, Gaetano; Cascone, Sara; Titomanlio, Giuseppe; Barba, Anna Angela Controlled Release of Drugs From Hydrogel Based Matrices Systems: Experiments and Modeling Journal Article Chemical and Biochemical Engineering Quarterly, 26 (4), pp. 321–330, 2012, ISSN: 0352-9568. Abstract | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @article{Lamberti2012c, title = {Controlled Release of Drugs From Hydrogel Based Matrices Systems: Experiments and Modeling}, author = { Gaetano Lamberti and Sara Cascone and Giuseppe Titomanlio and Anna Angela Barba}, issn = {0352-9568}, year = {2012}, date = {2012-01-01}, journal = {Chemical and Biochemical Engineering Quarterly}, volume = {26}, number = {4}, pages = {321--330}, publisher = {Hrvatsko dru\v{s}tvo kemijskih in\v{z}enjera i tehnologa}, abstract = {Hydrogels are materials largely used in the formulation of pharmaceuticals since, in principle, they could produce a release system of zero-order kinetics, which is of great therapeutic interest. In this paper, a model was proposed for the description of the main transport phenomena involved in the drug release process from hydrogel matrices (water diffusion, polymer swelling, drug diffusion and polymer dissolution); the model predictions are successfully compared with a large set of experimental data, obtained working with matrices systems based on HPMC (Hydroxy Propyl Methyl Cellulose). The proposed model was found able to reproduce main features of the observed phenomena, it can thus be adopted for prediction of the performances of drug release systems from hydrogel matrices.}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {article} } Hydrogels are materials largely used in the formulation of pharmaceuticals since, in principle, they could produce a release system of zero-order kinetics, which is of great therapeutic interest. In this paper, a model was proposed for the description of the main transport phenomena involved in the drug release process from hydrogel matrices (water diffusion, polymer swelling, drug diffusion and polymer dissolution); the model predictions are successfully compared with a large set of experimental data, obtained working with matrices systems based on HPMC (Hydroxy Propyl Methyl Cellulose). The proposed model was found able to reproduce main features of the observed phenomena, it can thus be adopted for prediction of the performances of drug release systems from hydrogel matrices. |
2010 |
Barba, Anna Angela; D'Amore, Matteo; Cascone, Sara; Lamberti, Gaetano; Rabbia, Luca; Titomanlio, Giuseppe; Grassi, Mario; Grassi, Gabriele Pluronic/alginate gels in drug eluting stents preparation Inproceedings Proceedings on CD-ROM of CHISA 2010 - ECCE 7, pp. 1–3, Chisa 2010, Praha, Czech Republic, 2010. BibTeX | Tags: Hydrogel Characterization @inproceedings{a.a.2010, title = {Pluronic/alginate gels in drug eluting stents preparation}, author = { Anna Angela Barba and Matteo D'Amore and Sara Cascone and Gaetano Lamberti and Luca Rabbia and Giuseppe Titomanlio and Mario Grassi and Gabriele Grassi}, year = {2010}, date = {2010-08-01}, booktitle = {Proceedings on CD-ROM of CHISA 2010 - ECCE 7}, pages = {1--3}, publisher = {Chisa 2010}, address = {Praha, Czech Republic}, keywords = {Hydrogel Characterization}, pubstate = {published}, tppubtype = {inproceedings} } |
Barba, Anna Angela; D'Amore, Matteo; Rabbia, Luca; Cascone, Sara; Lamberti, Gaetano; Titomanlio, Giuseppe; Grassi, Mario; Grassi, Gabriele Gelification of polymer blends for coating of eluting stents Inproceedings Proceedings of 7th World Meeting on Pharmaceutics, Biopharmaceutics and Pharmaceutical Technology, pp. 1–2, xxxx, Valletta (Malta), 2010, (Proc. su CD ROM). BibTeX | Tags: Hydrogel Characterization @inproceedings{a.2010-1, title = {Gelification of polymer blends for coating of eluting stents}, author = { Anna Angela Barba and Matteo D'Amore and Luca Rabbia and Sara Cascone and Gaetano Lamberti and Giuseppe Titomanlio and Mario Grassi and Gabriele Grassi}, year = {2010}, date = {2010-03-01}, booktitle = {Proceedings of 7th World Meeting on Pharmaceutics, Biopharmaceutics and Pharmaceutical Technology}, pages = {1--2}, publisher = {xxxx}, address = {Valletta (Malta)}, note = {Proc. su CD ROM}, keywords = {Hydrogel Characterization}, pubstate = {published}, tppubtype = {inproceedings} } |
2009 |
Barba, Anna Angela; D'Amore, Matteo; Cascone, Sara; Chirico, Serafina; Lamberti, Gaetano; Titomanlio, Giuseppe On the behavior of HPMC/Theophylline matrices for controlled drug delivery Journal Article Journal of Pharmaceutical Sciences, 98 (11), pp. 4100–4110, 2009, ISSN: 00223549. Abstract | Links | BibTeX | Tags: Diffusion, drug release, HPMC, Hydrogel Characterization, swellable hydrogels, Theophylline @article{Barba2009h, title = {On the behavior of HPMC/Theophylline matrices for controlled drug delivery}, author = { Anna Angela Barba and Matteo D'Amore and Sara Cascone and Serafina Chirico and Gaetano Lamberti and Giuseppe Titomanlio}, url = {http://doi.wiley.com/10.1002/jps.21701}, doi = {10.1002/jps.21701}, issn = {00223549}, year = {2009}, date = {2009-11-01}, journal = {Journal of Pharmaceutical Sciences}, volume = {98}, number = {11}, pages = {4100--4110}, publisher = {Wiley Subscription Services, Inc., A Wiley Company}, abstract = {Design of systems for oral controlled release of drug could take advantages from the knowledge of which phenomena take place. In this work matrices obtained by powders compression (50:50, hydroxypropyl methylcellulose, a swelling hydrogel, and theophylline, a model drug) were immersed in water at 37 degrees C, allowing the water uptake and the drug release by lateral surface, confining the cylindrical matrices between glass slides. The tablets, after given immersion times, were withdrawn, cut in several annuli, and subsequently analyzed for the drug and the water concentration radial profiles. The data confirmed the pseudo-diffusive nature of the process, allowing to give a deep insight into the drug release process from swellable hydrogel matrices. In particular, it was confirmed the presence of nonhomogeneous gel layer, rich in water and poor in drug, with a profile of drug concentration which agrees well with a pseudo-diffusion phenomenon.}, keywords = {Diffusion, drug release, HPMC, Hydrogel Characterization, swellable hydrogels, Theophylline}, pubstate = {published}, tppubtype = {article} } Design of systems for oral controlled release of drug could take advantages from the knowledge of which phenomena take place. In this work matrices obtained by powders compression (50:50, hydroxypropyl methylcellulose, a swelling hydrogel, and theophylline, a model drug) were immersed in water at 37 degrees C, allowing the water uptake and the drug release by lateral surface, confining the cylindrical matrices between glass slides. The tablets, after given immersion times, were withdrawn, cut in several annuli, and subsequently analyzed for the drug and the water concentration radial profiles. The data confirmed the pseudo-diffusive nature of the process, allowing to give a deep insight into the drug release process from swellable hydrogel matrices. In particular, it was confirmed the presence of nonhomogeneous gel layer, rich in water and poor in drug, with a profile of drug concentration which agrees well with a pseudo-diffusion phenomenon. |
Barba, Anna Angela; D'Amore, Matteo; Chirico, Serafina; Lamberti, Gaetano; Titomanlio, Giuseppe Swelling of cellulose derivative (HPMC) matrix systems for drug delivery Journal Article Carbohydrate Polymers, 78 (3), pp. 469–474, 2009, ISSN: 01448617. Abstract | Links | BibTeX | Tags: Erosion, Extended release, HPMC, Hydrogel Characterization, Swelling, Water diffusion @article{Barba2009f, title = {Swelling of cellulose derivative (HPMC) matrix systems for drug delivery}, author = { Anna Angela Barba and Matteo D'Amore and Serafina Chirico and Gaetano Lamberti and Giuseppe Titomanlio}, url = {http://www.sciencedirect.com/science/article/pii/S0144861709002707}, doi = {10.1016/j.carbpol.2009.05.001}, issn = {01448617}, year = {2009}, date = {2009-10-01}, journal = {Carbohydrate Polymers}, volume = {78}, number = {3}, pages = {469--474}, abstract = {The water swellable hydrogels are commonly used in the production of solid pharmaceutical dosage systems for oral administration (matrices). Their use allows to obtain the controlled drug release. The key role is played by the transport phenomena which take place: water up-take, gel swelling and erosion, increase in diffusivity due to hydration. Thus, knowledge of these phenomena is fundamental in designing and realizing the pharmaceutical systems. In this work, tablets made of pure hydrogel, HydroxyPropyl-MethylCellulose (HPMC), were produced and immersed in a thermostatic bath filled with stirred distilled water (37°C). The water up-take was allowed only by radial direction (from the lateral surface) by confining the tablet between two glass slides. Two distinct methods, an optical technique already described in a previous work, and a gravimetric procedure described here, were applied to measure the water concentration profiles along the radial direction in the tablets. The data obtained were used both to clarify the nature of the transport phenomena involved, and to perform a better tuning of a mathematical model previously proposed.}, keywords = {Erosion, Extended release, HPMC, Hydrogel Characterization, Swelling, Water diffusion}, pubstate = {published}, tppubtype = {article} } The water swellable hydrogels are commonly used in the production of solid pharmaceutical dosage systems for oral administration (matrices). Their use allows to obtain the controlled drug release. The key role is played by the transport phenomena which take place: water up-take, gel swelling and erosion, increase in diffusivity due to hydration. Thus, knowledge of these phenomena is fundamental in designing and realizing the pharmaceutical systems. In this work, tablets made of pure hydrogel, HydroxyPropyl-MethylCellulose (HPMC), were produced and immersed in a thermostatic bath filled with stirred distilled water (37°C). The water up-take was allowed only by radial direction (from the lateral surface) by confining the tablet between two glass slides. Two distinct methods, an optical technique already described in a previous work, and a gravimetric procedure described here, were applied to measure the water concentration profiles along the radial direction in the tablets. The data obtained were used both to clarify the nature of the transport phenomena involved, and to perform a better tuning of a mathematical model previously proposed. |
Barba, Anna Angela; D'Amore, Matteo; Grassi, Mario; Chirico, Serafina; Lamberti, Gaetano; Titomanlio, Giuseppe Investigation of Pluronic© F127-Water solutions phase transitions by DSC and dielectric spectroscopy Journal Article Journal of Applied Polymer Science, 114 (2), pp. 688–695, 2009, ISSN: 00218995. Abstract | Links | BibTeX | Tags: biological applications of polymers, block copolymers, dielectric properties, differential scanning calorimetry (DSC), gelation, Hydrogel Characterization @article{Barba2009e, title = {Investigation of Pluronic© F127-Water solutions phase transitions by DSC and dielectric spectroscopy}, author = { Anna Angela Barba and Matteo D'Amore and Mario Grassi and Serafina Chirico and Gaetano Lamberti and Giuseppe Titomanlio}, url = {http://doi.wiley.com/10.1002/app.30586}, doi = {10.1002/app.30586}, issn = {00218995}, year = {2009}, date = {2009-10-01}, journal = {Journal of Applied Polymer Science}, volume = {114}, number = {2}, pages = {688--695}, publisher = {Wiley Subscription Services, Inc., A Wiley Company}, abstract = {The water solutions of the block copolymers PEOn-PPOm-PEOn, known as pluronics, show a complex thermal behavior, since they are liquid at low temperature (5°C), and they can give soft gel when heated at body temperature (37°C). These properties are of great interest in biomedical applications. To properly design these applications, a prerequisite is the knowledge of the thermodynamics\textemdashhow much\textemdashand of the kinetics\textemdashhow fast\textemdashwith which these transformations take place. In this work, solutions of F127 (the copolymer for which n = 100 and m = 65) were studied by varying the concentration and the temperature and analyzing their behavior when heated under several heating rates. The studies were performed by differential scanning calorimetry (DCS) and dielectric spectroscopy. The investigations carried out under equilibrium conditions allowed us to determine the thermodynamics of the phase transitions, whereas the investigations carried out under varying conditions allowed us to quantify the kinetics of the phase transitions. Empirical models were also proposed to describe both the thermodynamics and the kinetics observed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009}, keywords = {biological applications of polymers, block copolymers, dielectric properties, differential scanning calorimetry (DSC), gelation, Hydrogel Characterization}, pubstate = {published}, tppubtype = {article} } The water solutions of the block copolymers PEOn-PPOm-PEOn, known as pluronics, show a complex thermal behavior, since they are liquid at low temperature (5°C), and they can give soft gel when heated at body temperature (37°C). These properties are of great interest in biomedical applications. To properly design these applications, a prerequisite is the knowledge of the thermodynamics—how much—and of the kinetics—how fast—with which these transformations take place. In this work, solutions of F127 (the copolymer for which n = 100 and m = 65) were studied by varying the concentration and the temperature and analyzing their behavior when heated under several heating rates. The studies were performed by differential scanning calorimetry (DCS) and dielectric spectroscopy. The investigations carried out under equilibrium conditions allowed us to determine the thermodynamics of the phase transitions, whereas the investigations carried out under varying conditions allowed us to quantify the kinetics of the phase transitions. Empirical models were also proposed to describe both the thermodynamics and the kinetics observed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 |
Barba, Anna Angela; Chirico, Serafina; Dalmoro, Annalisa; Galzerano, Barbara; Lamberti, Gaetano Water and drug mass fraction profiles in HPMC/TP matrices Inproceedings Proceedings of CRS36, pp. 1–4, Copenhagen, Danimarca, 2009. BibTeX | Tags: Hydrogel Characterization @inproceedings{barba2009-3, title = {Water and drug mass fraction profiles in HPMC/TP matrices}, author = { Anna Angela Barba and Serafina Chirico and Annalisa Dalmoro and Barbara Galzerano and Gaetano Lamberti}, year = {2009}, date = {2009-07-01}, booktitle = {Proceedings of CRS36}, pages = {1--4}, address = {Copenhagen, Danimarca}, keywords = {Hydrogel Characterization}, pubstate = {published}, tppubtype = {inproceedings} } |
Barba, Anna Angela; Chirico, Serafina; Dalmoro, Annalisa; Lamberti, Gaetano Simultaneous measurement of theophylline and cellulose acetate phthalate in phosphate buffer by UV analysis Journal Article Can J Anal Sci Spectros, 53 (6), pp. 249–253, 2009. Abstract | BibTeX | Tags: Hydrogel Characterization @article{Barba2009a, title = {Simultaneous measurement of theophylline and cellulose acetate phthalate in phosphate buffer by UV analysis}, author = { Anna Angela Barba and Serafina Chirico and Annalisa Dalmoro and Gaetano Lamberti}, year = {2009}, date = {2009-01-01}, journal = {Can J Anal Sci Spectros}, volume = {53}, number = {6}, pages = {249--253}, abstract = {The oral administration of pH-sensitive drugs requires protecting the drug molecules from the acidic pH in the stomach: the simplest way is to use polymers as coating, especially polymers which are insoluble at low pH (in the stomach) and soluble under neutral conditions (in the intestine). The Cellulose Acetate Phosphate, CAP, is one of these polymers, and it is one of the most used coating polymers. Studies related to the behavior of such pharmaceutical systems require fast and accurate methods to assay the released drug concentration in dissolution medium. However, both the drug and the coating polymer are present in the dissolution bulk with unknown concentration, and they can interfere each other in assaying. In this communication, a simple method to assay, by UV analysis, Theophylline (TP) and Cellulose Acetate Phosphate concentrations in a dissolution medium, phosphate buffer pH 7.0 (BP), is proposed and validated.}, keywords = {Hydrogel Characterization}, pubstate = {published}, tppubtype = {article} } The oral administration of pH-sensitive drugs requires protecting the drug molecules from the acidic pH in the stomach: the simplest way is to use polymers as coating, especially polymers which are insoluble at low pH (in the stomach) and soluble under neutral conditions (in the intestine). The Cellulose Acetate Phosphate, CAP, is one of these polymers, and it is one of the most used coating polymers. Studies related to the behavior of such pharmaceutical systems require fast and accurate methods to assay the released drug concentration in dissolution medium. However, both the drug and the coating polymer are present in the dissolution bulk with unknown concentration, and they can interfere each other in assaying. In this communication, a simple method to assay, by UV analysis, Theophylline (TP) and Cellulose Acetate Phosphate concentrations in a dissolution medium, phosphate buffer pH 7.0 (BP), is proposed and validated. |
Barba, Anna Angela; Lamberti, Gaetano Verso un rilascio intelligente Journal Article NCF-Notiziario Chimico Farmaceutico, 48 (1), pp. 68–71, 2009, ISSN: 0393-3733. Abstract | BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @article{Barba2009b, title = {Verso un rilascio intelligente}, author = { Anna Angela Barba and Gaetano Lamberti}, issn = {0393-3733}, year = {2009}, date = {2009-01-01}, journal = {NCF-Notiziario Chimico Farmaceutico}, volume = {48}, number = {1}, pages = {68--71}, abstract = {L’efficacia di una terapia farmacologica dipende molto dal profi lo di rilascio del principio attivo dalla forma farmaceutica selezionata. In riferimento alla via di somministrazione orale, comprendere i fenomeni che si verificano dopo l’ingestione di una compressa \'{e} un passaggio fondamentale per poter ottimizzare le formulazioni e le tecniche di preparazione. Investigare tali fenomeni \'{e} uno degli scopi della nostra ricerca, e nell’articolo sono presentati e discussi alcuni risultati selezionati.}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {article} } L’efficacia di una terapia farmacologica dipende molto dal profi lo di rilascio del principio attivo dalla forma farmaceutica selezionata. In riferimento alla via di somministrazione orale, comprendere i fenomeni che si verificano dopo l’ingestione di una compressa é un passaggio fondamentale per poter ottimizzare le formulazioni e le tecniche di preparazione. Investigare tali fenomeni é uno degli scopi della nostra ricerca, e nell’articolo sono presentati e discussi alcuni risultati selezionati. |
2008 |
Barba, Anna Angela; Chirico, Serafina; D'Amore, Matteo; Lamberti, Gaetano; Titomanlio, Giuseppe On the release of active molecules from hydrogels based tablets Inproceedings pp. 501, Salerno, Italia, 2008. BibTeX | Tags: Hydrogel Characterization @inproceedings{barba2008-7, title = {On the release of active molecules from hydrogels based tablets}, author = { Anna Angela Barba and Serafina Chirico and Matteo D'Amore and Gaetano Lamberti and Giuseppe Titomanlio}, year = {2008}, date = {2008-06-01}, pages = {501}, address = {Salerno, Italia}, keywords = {Hydrogel Characterization}, pubstate = {published}, tppubtype = {inproceedings} } |
Barba, Anna Angela; Chirico, Serafina; D'Amore, Matteo; Lamberti, Gaetano; LANZA, R F; Titomanlio, Giuseppe Transport phenomena in HPMC based tablets containing theophylline as drug Inproceedings Proceedings of 6th World Meeting on Pharmaceutics, Biopharmaceutics and Pharmaceutical Technology, pp. 1–4, Barcelona, Spain, 2008. BibTeX | Tags: Hydrogel Characterization @inproceedings{barba2008-6, title = {Transport phenomena in HPMC based tablets containing theophylline as drug}, author = { Anna Angela Barba and Serafina Chirico and Matteo D'Amore and Gaetano Lamberti and R.F LANZA and Giuseppe Titomanlio}, year = {2008}, date = {2008-04-01}, booktitle = {Proceedings of 6th World Meeting on Pharmaceutics, Biopharmaceutics and Pharmaceutical Technology}, pages = {1--4}, address = {Barcelona, Spain}, keywords = {Hydrogel Characterization}, pubstate = {published}, tppubtype = {inproceedings} } |
2007 |
Barba, Anna Angela; D'Amore, Matteo; Lamberti, Gaetano Analysis and modeling of Diclofenac Sodium release kinetics from HPMC tablets Inproceedings Proceedings of European Congress of Chemical Engineering (ECCE-6), pp. 253–254, Copenhagen, 2007. BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @inproceedings{barba2007, title = {Analysis and modeling of Diclofenac Sodium release kinetics from HPMC tablets}, author = { Anna Angela Barba and Matteo D'Amore and Gaetano Lamberti}, year = {2007}, date = {2007-09-01}, booktitle = {Proceedings of European Congress of Chemical Engineering (ECCE-6)}, pages = {253--254}, address = {Copenhagen}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {inproceedings} } |
0000 |
Barba, Anna Angela; Chirico, Serafina; D'Amore, Matteo; Lamberti, Gaetano; Titomanlio, Giuseppe Hydration, swelling , erosion and drug release from HPMC and HPMC/TP Inproceedings pp. 61–64, Piano di Sorrento (NA), Italia, 0000. BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @inproceedings{barba2008-4, title = {Hydration, swelling , erosion and drug release from HPMC and HPMC/TP}, author = { Anna Angela Barba and Serafina Chirico and Matteo D'Amore and Gaetano Lamberti and Giuseppe Titomanlio}, pages = {61--64}, address = {Piano di Sorrento (NA), Italia}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {inproceedings} } |
Barba, Anna Angela; D'Amore, Matteo; Chirico, Serafina; Lamberti, Gaetano; Titomanlio, Giuseppe Sul rilascio di molecole attive da compresse basate su idrogeli Inproceedings pp. 117–122, Crotone, Italia, 0000. BibTeX | Tags: Hydrogel Characterization @inproceedings{barba2008-3, title = {Sul rilascio di molecole attive da compresse basate su idrogeli}, author = { Anna Angela Barba and Matteo D'Amore and Serafina Chirico and Gaetano Lamberti and Giuseppe Titomanlio}, pages = {117--122}, address = {Crotone, Italia}, keywords = {Hydrogel Characterization}, pubstate = {published}, tppubtype = {inproceedings} } |
Barba, Anna Angela; D'Amore, Matteo; Lamberti, Gaetano Analysis of Mass Transfer during Controlled Release of Diclofenac from Commercial Tablets Inproceedings pp. x, Vienna (Austria), 0000. BibTeX | Tags: Hydrogel Characterization, Hydrogel Modeling @inproceedings{barba2006, title = {Analysis of Mass Transfer during Controlled Release of Diclofenac from Commercial Tablets}, author = { Anna Angela Barba and Matteo D'Amore and Gaetano Lamberti}, pages = {x}, address = {Vienna (Austria)}, keywords = {Hydrogel Characterization, Hydrogel Modeling}, pubstate = {published}, tppubtype = {inproceedings} } |