Question

In 1920s, Frederick Banting and James Collip purified insulin from bovine pancreas. Although it had been used to treat diabetic patients, it was not clear about the purity of those insulins. Equipped with the knowledge of chromatography methods, how can you figure out the purity level of those insulins? If it is not up to the FDA’s standard as a therapeutic drug, please give your suggestions to improve the purity of the insulins produced by the Toronto team.

Answer 1

Insulin needs to be extracted from the patient's serum and for liberating insulin B chain it will be reduced. Liquid chromatography helps achieving subsequent resolution of peptide. Quantification is done by B chain transition through monitoring selected reactions. Calibration is done by recombinant human insulin. Then it is compared with standard purity levels.

Insulin analogs comprising several orthogonal chromatographic purification processes followed by peptide insulin precursor's enzymatic digestion for removal of the specific impurities. This improves the purity of the produced insulins.