The Preparative Chromatography Standard is 5 mg/mL each of Diclofenac sodium salt, Diphenhydramine hydrochloride, and Flavone in DMSO. This standard mix should be used to confirm the benchmark performance of your Preparative/purification system. This particular QC Reference Material is a specially formulated mix that includes a void marker, neutral, acidic and basic compounds. It can be used with a variety of column chemistries and dimensions, and system hardware.