In this study, a redox-sensitive chitosan derivative with modifications by cholesterol, sulfhydryl, and mPEG (mPEG-CS(SH)-CHO) was successfully synthesized and characterized. Due to its amphiphilicity, the conjugate could spontaneously form micelles in an aqueous environment. The optimized paclitaxel (PTX)-loaded mPEG-CS(SH)-CHO micelles, with a mean diameter of 158 nm, zeta potential of +26.9 mV, drug loading of 11.7%, and entrapment efficiency of 88.3%, were successfully prepared. The results of an XRD study demonstrated that PTX was loaded in the core of the micelles in a non-crystalline state. Inspiringly, the PTX-loaded micelles possessed excellent anticancer effect but low toxicity to the body. It can be concluded that the mPEG-CS(SH)-CHO micellar system is a promising drug delivery carrier for the controlled release of PTX.
Keywords: chitosan; cholesterol; mPEG; micelles; redox-responsive.