Extraction method A significant portion of peptide drugs are extracted from plants and animals, such as insulin from the pig's pancreas. The polypeptide purity obtained by extraction method is low, and the content of peptide substances in the organism is very small, and the extraction process is easy to introduce animal pathogenic bacteria or viruses, thus limiting its application.
Therefore, the technique of bioextraction polypeptide has been gradually replaced by chemical synthesis or gene recombination technology.
Chemical synthesis Peptides are made up of amino acids, whether natural peptides produced by organisms or synthetic peptides, with different amino acids connected by amide bonds in a certain order. The amida bond has an amino acid amino acid amino base and another amino acid, the pyridine, which is removed from a water formation. Therefore, the chemical synthesis of peptides focuses on activating or protecting amino and pyridine in the right place and at the right time. The synthesis of peptides consists of three steps: step 1, protecting the active part of the reaction that does not participate in the reaction, step 2, activating the argon as an active intermediate, and step 3, de-protection of the protected group. The polypeptides to be synthesized are then purified by the high-efficiency liquid chromatography.