title: Chitosan gels for the vaginal delivery of lactic acid: relevance of formulation parameters to mucoadhesion and release mechanisms.
abstract: The aim of this work was to assess the effect of formulation parameters of a mucoadhesive vaginal gel based on chitosan and lactic acid, and to highlight its release mechanisms. Two molecular weight chitosans were used to prepare gels with 2 lactic acid concentrations. Both chitosan molecular weight and lactic acid concentration had a significant and mutually dependent influence on mucoadhesion, measured on pig vaginal mucosa. Similarly, the lactate release profiles were found to be dependent on lactic acid content and polymer molecular weight. One gel formulation based on the stoichiometric lactate to chitosan ratio was subjected to release test in media with 2 different counterions and increasing ionic strength. This test demonstrated that the lactate release is mainly due to ionic displacement.
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Pavia, Pavia, Italy. cbonferoni@unipv.it
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Bonferoni
authors.forename: Paolo
authors.initials: P
authors.lastname: Giunchedi
authors.forename: Santo
authors.initials: S
authors.lastname: Scalia
authors.forename: Silvia
authors.initials: S
authors.lastname: Rossi
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Sandri
authors.forename: Carla
authors.initials: C
authors.lastname: Caramella
mesh_terms: D000268:Adhesiveness; D000282:Administration, Intravaginal; D000818:Animals; D048271:Chitosan / Q000737:chemistry*; D004337:Drug Carriers / Q000008:administration & dosage / Q000737:chemistry*; D004339:Drug Compounding / Q000379:methods; D004355:Drug Stability; D004548:Elasticity; D005260:Female; D066298:In Vitro Techniques; D019344:Lactic Acid / Q000008:administration & dosage / Q000737:chemistry*; D008422:Materials Testing; D009092:Mucous Membrane / Q000737:chemistry*; D013552:Swine; D013718:Tensile Strength; D014621:Vagina / Q000737:chemistry*; D014622:Vaginal Creams, Foams, and Jellies / Q000008:administration & dosage* / Q000737:chemistry*; D014783:Viscosity
chemical_list: D004337:Drug Carriers; D014622:Vaginal Creams, Foams, and Jellies; D019344:Lactic Acid; D048271:Chitosan