2.7. Sulforhodamine B (SRB) Cell Viability Assay

Hep-J5 wild-type (WT) or α7-nAChR-KD cells were seeded at a density of 3 × 10³ cells/well in 96-well plates, then incubated in humidified 5% CO₂ at 37 °C for 24 or 48 h. After 24 or 48 h, HCC cells were fixed in 10% trichloroacetic acid (TCA), then washed with double-distilled (dd)H₂O, before viable cells were stained with 0.4% SRB in 1% acetic acid. The free dye was removed by repeated washings with 1% acetic acid before air-drying the plates, while the bound dye was dissolved in 10 mM Trizma, and the absorbance was read at a 495-nm wavelength in a microplate reader.