Peptide Synthesis

A peptide consists of two or more amino acids linked by an amide bond, to form a chain of amino acids typically 2 – 70 amino-acids long. Peptides are distinguished from proteins by not requiring to be folded for biological activity. Peptides occur endogenously as peptide hormones, such as angiotension, LHRH, enkephalin, and as toxins in plants and animals. Peptides are of great interest as lead compounds for drug discovery and as drugs in their own right. They also find applications in vaccines, biomaterials, histological probes and are used in large numbers as antigens to generate antibodies. 

Peptides are synthesized chemically either in solution or on a solid phase. The process involves directed and selective formation of an amide bond between an N-protected amino acid and an amino acid bearing a free amino group and protected carboxylic acid. In solid phase synthesis, the carboxyl protecting group is linked to a polymer support. Following bond formation, the amino-protecting group of the dipeptide is removed, and the next N-protected amino-acid is coupled.