Totally S-protected hyaluronic acid: evaluation of stability and mucoadhesive properties as liquid dosage form
AIM
It is the aim of this study to synthesize hyaluronic acid (HA) derivatives bearing mucoadhesive properties and showing prolonged stability at pH 7.4 and under oxidative condition as liquid dosage form.
METHODS
HA was modified by thiolation with L-cysteine (HA-SH) and by conjugation with 2-mercaptonicotinic acid-L-cysteine ligand to obtain an S-protected derivative (HA-MNA). The polymers were characterized by determination of thiol group content and mercaptonicotinic acid content. Cytotoxicity, stability and mucoadhesive properties (rheological evaluation and tensile test) of the polymers were evaluated.