Cytotoxicity Evaluation of Honey and Honey-AgNPs

Additionally, 96-well plates were seeded with MCF-7, HeLa, and HePG2 cells, at approximately 105/well. Following 72 h exposure to honey and honey with AgNPs, the medium was changed to 150 L of 10% trichloroacetic acid (TCA) from Merck for 1 h at 4 °C; then, the cultures were washed five times with distilled water. Afterward, a 70 μL SRB solution (0.4% w/v) (Sigma Aldrich, St. Louis, MO, USA) was added for 10 min at room temperature in a dark location. The cells were washed three times with 1% acetic acid (Merck) and left overnight to air dry. The protein-bound SRB stain was dissolved by adding 150 μL of 10 mM Tris Base (Merck), and the O.D. was measured at 540 nm using a FluoStar Omega microplate reader (BMG Labtec, Ortenberg, Germany) [51 (link)].