Chrysophanol (Turkey Rhubarb) is an EGFR/mTOR pathway inhibitor, which can be found in rhubarb, and sorrel.

Chrysophanol (Chrysophanic Acid) is dissolved in DMSO and stored, and then diluted with appropriate medium before use[1]. The cells are seeded at 5×103 cells/mL in 96-well microplates and allowed to attach for 24 h. Chrysophanol (20, 50, 80 and 120 μM) is added to the medium at various concentrations up to 120 μM and for different durations. After treatment, cell cytotoxicity and/or proliferation is assessed by a Cell Counting Kit-8 (CCK-8). Briefly, highly water-soluble tetrazolium salt, WST-8, produces an orange colored water-soluble product, formazan. The amount of formazan dye generated by dehydrogenases in cells is directly proportional to the number of living cells.CCK-8 (10 μL) is added to each well and incubated for 3 h at 37°C, then cell proliferation and cytotoxicity are assessed by measuring the absorbance at 450 nm using a microplate reader.Three replicated wells are used for each experimental condition[1].

H2O: < 1 mg/mL (insoluble or slightly soluble)

Ethanol: < 1 mg/mL (insoluble or slightly soluble)

DMSO: 1.64 mg/mL (6.45 mM), Sonication is recommended.