B2 Microglobulin Human Recombinant produced in E.Coli is a non-glycosylated polypeptide chain having a molecular mass of 11.76 kDa. The B2M is purified by proprietary chromatographic techniques. The protein was lyophilized from a concentrated solution (1mg/ml) containing PBS (pH 7.4) and 0.05% NaN3.