Oil Red O Staining

Oil red O staining solution can identify adipocytes because the lipid droplets within the cell can be stained red, but other cells cannot. Oil red O staining occurs on the 12th day when the cells are growing, which is the eighth day when the cells start to differentiate. The adipocytes were washed with PBS buffer three times and fixed with 4% paraformaldehyde solution (Sangon Biotech Co., Ltd., Shanghai, China) in a 37°C and 5% CO₂ incubator for 30 min. The cells were washed with PBS buffer three times, then cells were treated with Oil red O (Sigma) for 30 min in the incubator. After this, the cells were washed with PBS buffer three times, the staining was observed with a microscope, and pictures were taken.