HEPES Buffer, 1M

HEPES Buffer, 1M, is prepared from HEPES Free acid with sterile-filtered, Molecular Biology grade water and is a biological buffer (zwitterionic) designed by Good, et al., and typically referred to as Good's buffer useful in cell culture media formulations. Selection of biological buffer systems should include the following criteria: exclusion by biological membranes, low absorption between 240 and 700nm, chemically stable, and stable to temperature and concentration changes. Appearance: Colorless, clear liquid , Purity:, >99%, pH: 4.60-6.50, pKa1: ~3, pKa2: 7.55 (at 20°C), Heavy Metals: <0.0001%, RNase, DNase, Protease: None Detected, Endotoxin: <1Eu/ml