||Recombinant Human Interferon-α1b produced inE.coliis a single non-glycosylated polypeptide chain containing 166 amino acids and having a molecular mass of approximately 19 kDa
||At least 23 different variants of IFN-alpha are known. The individual proteins have molecular masses between 19-26 kDa and consist of proteins with lengths of 156-166 and 172 amino acids. All IFN-alpha subtypes possess a common conserved sequence region between amino acid positions 115-151 while the amino-terminal ends are variable. Many IFN-alpha subtypes differ in their sequences at only one or two positions. Naturally occurring variants also include proteins truncated by 10 amino acids at the carboxy-terminal end.
||>96% by SDS-PAGE and HPLC analyses.
||Sterile Filtered White lyophilized (freeze-dried) powder.
||Lyophilized from a 0.2μm filtered concentrated (1mg/ml) solution in PBS, pH 7.4.
||Fully biologically active when compared to standard. The specific activity as determined in a viral resistance assay was found to be no less than 1.0 x 108IU/mg.
||Less than 1EU/μg of rHuIFN-α1b as determined by LAL method.
||We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1.0 mg/ml. Stock solutions should be apportioned into working aliquots and stored at <-20°C. Further dilutions should be made in appropriate buffered solutions.
||This lyophilized preparation is stable for several weeks at 2-8°C, but should be kept at -20°C for long term storage, preferably desiccated. Upon reconstitution, the preparation is stable for up to one week at 2-8°C. For maximal stability, apportion the reconstituted preparation into working aliquots and store at -20°C to -70°C. Avoid repeated freeze/thaw cycles.