Question: can dpph dissolve in water?
Answer: A stock solution may be made by dissolving the DPPH in the solvent of choice. DPPH is soluble in organic solvents such as ethanol and dimethyl formamide, which should be purged with an inert gas. The solubility of DPPH in these solvents is approximately 10 mg/ml. DPPH is sparingly soluble in aqueous solutions.