title: Chitosan and a modified chitosan as agents to improve performances of mucoadhesive vaginal gels.
abstract: New mucoadhesive formulations were designed and studied in order to improve local vaginal therapy by increasing formulation retention prolonging thus drug-mucosa contact time. Some gels were prepared using hydroxyethylcellulose (HEC) alone or mixed with chitosan (CS) or its derivative 5-methyl-pyrrolidinone-chitosan (MPCS) and were loaded with the antibacterial metronidazole (MET) (0.75%). All formulations showed pseudoplastic flow and viscosity increase was observed proportionally to chitosan content (CS>MPCS). Prepared gels showed better extrusion properties (yield stress) than market formulation Zidoval. Mucoadhesion force studies permitted to point out that: (i) CS decreases mucoadhesion force; (ii) MPCS addition increases the mucoadhesion force at high percentage; (iii) all gels containing chitosan showed better mucoadhesive performances than Zidoval. Gels containing MPCS showed higher and faster drug release than those containing CS. All the preparations were able to release higher drug amounts if compared to market formulation. In conclusion MPCS improved gel characteristics in terms of mucoadhesion force, rheological behaviour and drug release pointing out that this modified chitosan is very suitable to obtain manageable and more acceptable vaginal formulation.
authors.affiliation: Dipartimento di Chimica e Tecnologia del Farmaco, Università degli Studi di Perugia, Via del Liceo 1, Perugia 06123, Italy. luanaper@unipg.it
authors.forename: Luana
authors.initials: L
authors.lastname: Perioli
authors.forename: Valeria
authors.initials: V
authors.lastname: Ambrogi
authors.forename: Lorena
authors.initials: L
authors.lastname: Venezia
authors.forename: Cinzia
authors.initials: C
authors.lastname: Pagano
authors.forename: Maurizio
authors.initials: M
authors.lastname: Ricci
authors.forename: Carlo
authors.initials: C
authors.lastname: Rossi
mesh_terms: D000268:Adhesiveness; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002482:Cellulose / Q000031:analogs & derivatives* / Q000737:chemistry; D048271:Chitosan / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry*; D016503:Drug Delivery Systems; D004355:Drug Stability; D005260:Female; D009092:Mucous Membrane / Q000737:chemistry / Q000378:metabolism*; D011760:Pyrrolidinones / Q000737:chemistry*; D012212:Rheology; D013552:Swine; D014622:Vaginal Creams, Foams, and Jellies / Q000494:pharmacology*; D014783:Viscosity
chemical_list: D000900:Anti-Bacterial Agents; D004337:Drug Carriers; D011760:Pyrrolidinones; D014622:Vaginal Creams, Foams, and Jellies; C085060:methylpyrrolidinone chitosan; D002482:Cellulose; C002283:hydroxyethylcellulose; D048271:Chitosan