2.10. Immunofluorescence microscopy

Immunofluorescence was performed to observe the expression level of γ‐H2AX in the nuclei of cells in different treatment groups. The cells were fixed with 4% paraformaldehyde for 15 minutes at room temperature and permeabilized with 0.1% Triton X‐100. After blocking in PBS containing 5% BSA for 1 hours, the cells were incubated with anti‐γ‐H2AX primary antibodies and stained with FITC‐conjugated secondary antibodies. Nuclei were stained with DAPI for 15 minutes. The mean number of immunostained nuclei per high‐power field was determined using immunofluorescence microscopy. Results are presented as the average of at least three fields.