Mucoadhesive Polymer Hyaluronan as Biodegradable Cationic/Zwitterionic Drug Delivery Vehicle

The study from 2015 by Francisco Torrens and Gloria Castellano investigated the use of mucoadhesive polymers, specifically Hyaluronan (HA), in pharmaceutical formulations for drug delivery. The researchers found that these polymers, which release drugs in mucosal areas and increase drug bioavailability, have their mucoadhesion, rheological behaviour, and drug absorption affected by their physicochemical properties. The study used geometric, topological, and fractal analyses to examine HA and found that the hydrophobic term of HA increased by 42% and decreased by 26% when going from hexamer HA to HA·3Ca and hydrate, while the hydrophilic part dropped by 14% and rose by 58%. The study concluded that the exchange of cations in HA·3Ca requires alteration of Ca2+, and increases in the zwitterionic character of the drug and acidic pH enhance absorption.