Chitosan gels for the vaginal delivery of lactic acid: relevance of formulation parameters to mucoadhesion and release mechanisms.
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.
Bonferoni
Maria Cristina
MC
Department of Pharmaceutical Chemistry, School of Pharmacy, University of Pavia, Pavia, Italy. cbonferoni@unipv.it
Giunchedi
Paolo
P
Scalia
Santo
S
Rossi
Silvia
S
Sandri
Giuseppina
G
Caramella
Carla
C
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
D004337:Drug Carriers; D014622:Vaginal Creams, Foams, and Jellies; D019344:Lactic Acid; D048271:Chitosan