title: Tuning the Hydrophilic/Hydrophobic Balance to Control the Structure of Chitosan Films and Their Protein Release Behavior.
abstract: The control over the crystallinity of chitosan and chitosan/ovalbumin films can be achieved via an appropriate balance of the hydrophilic/hydrophobic interactions during the film formation process, which then controls the release kinetics of ovalbumin. Chitosan films were prepared by solvent casting. The presence of the anhydrous allomorph can be viewed as a probe of the hydrophobic conditions at the neutralization step. The semicrystalline structure, the swelling behavior of the films, the protein/chitosan interactions, and the release behavior of the films were impacted by the DA and the film processing parameters. At low DAs, the chitosan films neutralized in the solid state corresponded to the most hydrophobic environment, inducing the crystallization of the anhydrous allomorph with and without protein. The most hydrophilic conditions, leading to the hydrated allomorph, corresponded to non-neutralized films for the highest DAs. For the non-neutralized chitosan acetate (amorphous) films, the swelling increased when the DA decreased, whereas for the neutralized chitosan films, the swelling decreased. The in vitro release of ovalbumin (model protein) from chitosan films was controlled by their swelling behavior. For fast swelling films (DA = 45%), a burst effect was observed. On the contrary, a lag time was evidenced for DA = 2.5% with a limited release of the protein. Furthermore, by blending chitosans (DA = 2.5% and 45%), the release behavior was improved by reducing the burst effect and the lag time. The secondary structure of ovalbumin was partially maintained in the solid state, and the ovalbumin was released under its native form.
authors.affiliation: Ingénierie des Matériaux Polymères, CNRS UMR 5223, Univ Lyon, Université Claude Bernard Lyon 1, 15 bd Latarjet, 69622, Villeurbanne Cedex, France.
authors.forename: Jose
authors.initials: J
authors.lastname: Becerra
authors.affiliation: Ingénierie des Matériaux Polymères, CNRS UMR 5223, Univ Lyon, Université Claude Bernard Lyon 1, 15 bd Latarjet, 69622, Villeurbanne Cedex, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Sudre
authors.affiliation: Ingénierie des Matériaux Polymères, CNRS UMR 5223, Univ Lyon, Université Claude Bernard Lyon 1, 15 bd Latarjet, 69622, Villeurbanne Cedex, France.|Institut Jean Lamour, CNRS UMR 7198, Université de Lorraine, Parc de Saurupt CS 50840, 54011, Nancy Cedex, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Royaud
authors.affiliation: Institut de Biologie et Chimie des Protéines (IBCP), Bases Moléculaire et Structurales des Systèmes Infectieux, UMR 5086, 7 passage du Vercors, 69367, Lyon cedex 07, France.
authors.forename: Roland
authors.initials: R
authors.lastname: Montserret
authors.affiliation: Institut de Biologie et Chimie des Protéines (IBCP), Bases Moléculaire et Structurales des Systèmes Infectieux, UMR 5086, 7 passage du Vercors, 69367, Lyon cedex 07, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Verrier
authors.affiliation: CERMAV, Univ. Grenoble Alpes, 38000, Grenoble, France.|CERMAV, CNRS, 38000, Grenoble, France.
authors.forename: Cyrille
authors.initials: C
authors.lastname: Rochas
authors.affiliation: Ingénierie des Matériaux Polymères, CNRS UMR 5223, Univ Lyon, Université Claude Bernard Lyon 1, 15 bd Latarjet, 69622, Villeurbanne Cedex, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Delair
authors.affiliation: Ingénierie des Matériaux Polymères, CNRS UMR 5223, Univ Lyon, Université Claude Bernard Lyon 1, 15 bd Latarjet, 69622, Villeurbanne Cedex, France. laurent.david@univ-lyon1.fr.
authors.forename: Laurent
authors.initials: L
authors.lastname: David
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology; D048271:Chitosan / Q000737:chemistry / Q000494:pharmacology; D003460:Crystallization; D016503:Drug Delivery Systems; D057927:Hydrophobic and Hydrophilic Interactions; D010047:Ovalbumin / Q000737:chemistry / Q000493:pharmacokinetics
chemical_list: D001672:Biocompatible Materials; D010047:Ovalbumin; D048271:Chitosan
keywords: chitosan; crystalline allomorphs; films; ovalbumin; release kinetics