Self-assembly of biotinylated poly(ethylene glycol)-poly(curcumin) for paclitaxel delivery

Paclitaxel (PTX), one of the most potent anticancer agents, has showed a remarkable activity against varieties of tumors. However, the bioavailability of PTX is quite low due to its poor aqueous solubility. Moreover, the emerging multidrug resistance (MDR) in cancer to PTX remains a major obstacle for successful chemotherapy. In order to address these problems, we developed self-assembly of biotinylated poly(ethylene glycol)-poly(curcumin) (Biotin-PEG-PCDA) for PTX delivery (termed as PTX-BPC NPs) with the application of mPEG_2K-P(CL-co-LLA) as an emulsifier. The loading content and encapsulation efficiency of PTX were 13.2% and 92.0%, respectively. In vitro drug release study showed that PTX-BPC NPs could degrade rapidly and then release the PTX payload in a 10 mM glutathione (GSH) environment. Compared with free PTX, PTX-BPC NPs exhibited enhanced anticancer efficacy (IC_{50(MCF-7/ADR cells)}, 17.28 µg/mL vs. 1.15 µg/mL). In addition, these biotin-modified nanoparticles could also significantly reverse PTX resistance by suppressing the over-expression of P-gp, thus resulting in increased intracellular drug accumulation and reduced drug efflux in MCF-7/ADR cells, which showed a great anticancer effect.