Mucoadhesivity and release properties of quaternary ammonium-chitosan conjugates and their nanoparticulate supramolecular aggregates: An NMR investigation

Selective relaxation rate measurements effectively proved the affinity of dexamethasone 21-phosphate disodium salt for quaternary ammonium-chitosan conjugates, their thiolated derivatives and the corresponding nanostructured aggregates. Affinity was also probed by dynamic dialysis. The release profile of dexamethasone loaded nanoparticles was defined by quantitative NMR and interrupted dialysis experiments, and mucoadhesivity of empty nanoparticles was effectively probed by selective relaxation rate measurements. (C) 2014 Published by Elsevier B.V.