Fig. 6

a The cell viability of different formulations was analyzed by CCK-8 (a: PTX-Sol, b: GA-Sol, c: PTX + GA-Sol, d: PTX-NLC, e: GA-NLC, f: GA/PTX-NLC, g: RGE-GA/PTX-NLC, h: R9dGR-GA/PTX-NLC and i: blank NLC; GA = 0.4 μmol/L and PTX = 0.25 μmol/L). b, c MCF-7 and MCF-7/ADR cells was treated with different concentrations of GA and verapamil, then the P-gp activities were determined using a fluorometric MDR assay kit, μM stands for μmol/L. d, e Effects of GA-Sol and verapamil on cellular accumulation of Rh-123 in MCF-7 and MCF-7/ADR cells, μM stands for μmol/L. Results are expressed as mean ± SD, n = 3