Description: Recombinant Human Interferon-alpha 2b produced in E. coli is a single, non-glycosylated, polypeptide chain containing 165 amino acids and having a molecular mass of 19269 Dalton. The Interferon-alpha 2b gene was obtained from human leukocytes. Quality Control: Biological activity: The specific activity as determined in a viral resistance assay using VSV- WISH cells was found to be greater than 1.0 x 108 IU/ mg. Purity: Greater than 95% as determined by (a) Analysis by SEC-HPLC. (b) Analysis by reducing and non-reducing SDS-PAGE Silver Stained gel. Molecular weight: 19.2KD+/-10% determined by reduced SDS-PAGE. Isoelectric Point: The main zone between 5.5~6.8 analysis by IEF. UV Scan: The maximal absorption wave is 278+/-3nm.