Self-aggregated nanoparticles of carboxylic curdlan-deoxycholic acid conjugates as a carrier of doxorubicin.

In this study, a new non-toxic, biodegradable, biocompatible and water-soluble carboxylic curdlan bearing the dissociable COOH group in 100% purity, which was prepared by 4-acetamido-TEMPO-mediated oxidation, was hydrophobically modified by deoxycholic acid (DOCA) to attain novel amphiphilic curdlan derivatives (CCDs) for the preparation of nano-carriers for antitumor drug doxorubicin (DOX). Under the effect of ultrasonication, the carboxylic curdlan derivatives in water were self-aggregated into spherical nanoparticles with diameters ranging from 214 nm to 380 nm. The critical aggregation concentrations decreased from 0.047 mg/mL to 0.016 mg/mL with increasing DS of DOCA. DOX-loaded CCD nanoparticles were prepared in an aqueous medium with dialysis method. The DOX-CCD nanoparticles exhibited pH- and dose-dependent drug release profiles during in vitro release experiments. Moreover, the drug transport mechanism was Fickian diffusion according to the Ritger-Peppas model. The CCD nanoparticles might be explored as potential carriers for hydrophobic drugs with controlled release and delivery functions.