N-acetylcysteine modified hyaluronic acid-paclitaxel conjugate for efficient oral chemotherapy through mucosal bioadhesion ability.

N-acetylcysteine modified hyaluronic acid-paclitaxel (NAC-HA-PTX) conjugate was designed to improve the water solubility and oral bioavailability of PTX through mucosal bioadhesion ability. The average size of spherical NAC-HA-PTX micelles was 187 nm with a zeta potential of -25.38 mV. Mucin adhesion study showed that the amount of mucin adhered to NAC-HA-PTX micelles was 1.98-fold greater than that of hyaluronic acid-paclitaxel (HA-PTX) micelles. The fluorescence micrographs showed that the biodistribution sequence of coumarin 6-loaded micelles in the gastrointestinal tract was duodenum > jejunum > ileum, and NAC-modified micelles significantly exhibited better mucoadhesive properties than the corresponding unmodified ones. The pharmacokinetic study showed that the area under the curve (AUC0-24h) of NAC-HA-PTX micelles was 2.32-fold and 2.56-fold higher compared to that of HA-PTX micelles and PTX solution (Taxol) after oral administration, respectively. NAC-HA-PTX micelles appear to be a promising drug delivery system to improve the bioavailability of insoluble drugs for efficient tumor therapy via oral administration.