title: Preactivated hyaluronic acid: A potential mucoadhesive polymer for vaginal delivery.
abstract: The objective of this study was to develop mucoadhesive polymeric excipients for vaginal drug delivery systems. Hyaluronic acid was thiolated and subsequently preactivated with 6-mercaptonicotinamide (HA-CYS-MNA) to enhance stability and mucoadhesive properties on vaginal mucosa. After determination of the thiol group content, disintegration studies and in vitro mucoadhesion studies (rotating cylinder and tensile) were performed. Furthermore, swelling behavior and cytotoxicity studies were performed in comparison with corresponding polymers. Both, disintegration and in vitro mucoadhesive studies revealed that modifying HA-CYS with MNA resulted in higher stability (3.6-fold prolonged disintegration time compared to unmodified hyaluronic acid) and prolonged mucoadhesion time. MTT assay and LDH revealed no toxicity for the polymeric excipients and safe for their use. Disintegration and swelling results conducted more pronounced stability of the preactivated thiomers compared to corresponding unmodified ones. According to these results preactivated hyaluronic acid might be a useful tool for vaginal delivery systems.
authors.affiliation: Department of Pharmaceutical Technology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Austria.
authors.forename: Jessika
authors.initials: J
authors.lastname: Nowak
authors.affiliation: Department of Pharmaceutical Technology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Austria.
authors.forename: Flavia
authors.initials: F
authors.lastname: Laffleur
authors.affiliation: Department of Pharmaceutical Technology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Austria. Electronic address: Andreas.bernkop@uibk.ac.at.
authors.forename: Andreas
authors.initials: A
authors.lastname: Bernkop-Schnürch
mesh_terms: D000268:Adhesiveness; D000282:Administration, Intravaginal; D000818:Animals; D018938:Caco-2 Cells; D002417:Cattle; D002470:Cell Survival / Q000187:drug effects; D016503:Drug Delivery Systems; D005079:Excipients / Q000737:chemistry; D005260:Female; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage / Q000737:chemistry*; D009092:Mucous Membrane / Q000737:chemistry; D009536:Niacinamide / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000008:administration & dosage / Q000737:chemistry*; D013607:Tablets; D013718:Tensile Strength
chemical_list: D005079:Excipients; D011108:Polymers; D013438:Sulfhydryl Compounds; D013607:Tablets; D009536:Niacinamide; D006820:Hyaluronic Acid
keywords: Hyaluronic acid; Mucoadhesion; Preactivated thiomers; Thiomers; Vaginal delivery