50 mg/ml Rifampicin in DMSO Weigh 0.5 g of rifampicin (Rifampicin, GoldBio Catalog # R-120, [CAS 13292-46-1, mw. = 822.94 g/mol]). Add 10 ml DMSO. Dissolve completely. Stock may be kept at -20°C for 1 year. Rifampicin may precipitate in the freezer. Dissolve again before use. 16 mg/ml Rifampicin in Methanol Weigh 0.16 g of rifampicin [Rifampicin, GoldBio Catalog # R-120, (CAS 13292-46-1, MW = 822.94 g/mol)]. Add 10 ml Methanol. Dissolve completely. Stock may be kept at -20°C for 1 year. Rifampicin may precipitate in the freezer. Dissolve again before use. Note: Rifampicin will precipitate out of solution in methanol if the concentration is above 16 mg/ml.
