2.10. Oil Red O staining

Oil Red O powder (350 mg) was dissolved in 100 mL 100% isopropanol as a stock solution. Working solutions were prepared by mixing 60% stock with 40% H₂O, vortexing, and resting for 30 min at room temperature before filtering through a 0.2 μm filter. Cells were washed twice in PBS, fixed in 4% paraformaldehyde for 15 min, and then incubated with the Oil Red O working solution for 30 min at room temperature. Three more PBS washes were performed before cells were counterstained with hematoxylin and coverslipped for imaging.