Storage: Store at or below -20 ??C. Solubility: Soluble in DMSO at 20 mg/mL; soluble in ethanol at 2.5 mg/mL with warming; very poorly soluble in water; maximum solubility in plain water is estimated to be about 1-5 ??M; buffers, serum, or other additives may increase or decrease the aqueous solubility.