Wound Healing Assay for MCF-7 Cells

The MCF-7 cell lines were first grown in DMEM supplemented with 10% FBS to test migration assay, then seeded in 6-well plates.^{19 (link)} Next, the width of each well is scratched by sterile pipette tip (1 mm). The wells are washed by the culture medium and the picture of wounds is taken at 0 hour (NIKON, Inverted research microscope). Thereafter, medium was replaced with different concentrations of PLGA-PTX-VitD₃ co-delivery NPs, PTX and PLGA-PTX (IC₅₀ concentration) and the cells are allowed to migrate for 24 hours. After 24 hours, the picture of wound is taken from the same regions. The rate of migration (R_M) is analyzed by measuring the distance between the scratch edges with digitizer software. The R_M is calculated by following equation: R_M=(W_i-W_f)/t.^{20 (link)}