EVALUATION OF THE BIOADHESIVE PROPERTIES OF HYALURONAN DERIVATIVES - DETACHMENT WEIGHT AND MUCOCILIARY TRANSPORT RATE STUDIES

Hyaluronan of various molecular weights, and microspheres made from se veral of its esters, were assessed for adhesiveness in vitro by means of detachment weight and mucociliary transport rate. Microspheres made from esters of alginic acid and gellan gum were also evaluated. The r esults were compared with those obtained from Carbopol 974 which was u sed as a positive control. Hyaluronan and its autocross-linked esters displayed comparable adhesion to Carbopol in both studies. All microsp here preparations were less adhesive than Carbopol (p < 0.05, Mann-Whi tney U-test) when tested for detachment weight (using mucosal epitheli um)) and mucociliary transport rate. Adhesion to a mucus gel was simil ar for most preparations. Hyaluronan has been shown to possess excelle nt adhesion in vitro, Although formulation of hyaluronan into microsph eres tends to reduce its inherent adhesive properties, the microsphere s formed displayed significantly decreased mucociliary clearance. The inclusion of drug into such a biodegradable and biocompatible dosage f orm is an attractive prospect for transmucosal delivery.