Abstract: Objective To explore whether quercetin-loaded PEG-PE micelles(M-Q) will synergize the growth-inhibitory activity of adriamycin(ADR)by reversing the drug resistance of MCF-7 ADRr breast cancer cells in vitro. Methods M-Q were formed by adding saline to lipid film containing quercetin and PEG-PE. The size of M-Q was characterized by dynamic light scattering(DLS). The inhibition of MCF-7 ADRr cells was evaluated by MTS assay after incubation with M-Q and ADR. Results The incorporation efficiency of quercetin by the micelles was above 74%.The average size of M-Q was 11.11nm. Compared with the quercetin dissolved in ethanol, M-Q more effectively reversed the drug resistance of MCF-7 ADRr cells in vitro. Conclusions PEG-PE micelles may have potential for delivering quercetin to cancer cells for reversal of drug resistance.

Key words: PEG-PE, micelles, quercetin, MCF-7 ADRr cells