The Effect Of Thiol Content On The Gelation And Mucoadhesion Of Thiolated Poly(Aspartic Acid)

A synthetic poly(amino acid), poly(aspartic acid) modified with thioethyl side groups, was studied as an in situ gelling and mucoadhesive dosage form. The chemical structure and the controllable, large thiol content of the polymer were confirmed using H-1 NMR spectroscopy and Ellman's assay. In situ gelation of aqueous polymer solutions was induced by oxidation and monitored using oscillation rheometry. The strength of mucoadhesion towards excised mucosa was characterised by tensile tests in ex vivo experiments. Release kinetics of ophthalmic antibiotic ofloxacin was studied from an in situ crosslinked hydrogel and a liquid formulation to prove the sustained release of the former. (C) 2017 Society of Chemical Industry