The process of turning amino acid chains into peptides is known as peptide synthesis. These peptides can have chains that are much longer than a few amino acids or just a few. Peptides have many uses in industry, research, and medicine and are essential to many biological processes. Solid-phase peptide synthesis (SPPS) and liquid-phase peptide synthesis (LPPS) are the two main techniques for synthesizing peptides. Because to its efficiency and adaptability, solid-phase peptide synthesis (SPPS) is the most widely used technique. The peptide chain in SPPS is constructed on a firm support, usually a resin bead. Attached to the resin is the first amino acid, which is protected at its N-terminus. At this point, the protective group stops unintended reactions. Using coupling reagents, successive amino acids are added one at a time, each with its own protective group. By activating the carboxyl group of the incoming amino acid, these chemicals enable it to react with the developing chain's amino group. To stop side reactions, the unreacted amino groups are capped after each coupling step. Until the desired peptide sequence is obtained, this process is repeated. Ultimately, the pure peptide product is obtained by cleaving the peptide from the resin and removing the protective groups.On the other hand, peptides are synthesized via liquid-phase peptide synthesis (LPPS), which does not require a solid substrate. Although it can be applied to shorter peptides, the problems in purifying and isolating the developing peptide from undesirable side products make it less effective for longer sequences. The preservation of functional groups is an essential component in peptide synthesis. Protecting groups are employed to make sure that reactions only happen at the intended sites because amino acids have several reactive sites. For the amino group and side chains, respectively, common protective groups are Boc (tert-butyloxycarbonyl) and Fmoc (9-fluorenylmethyloxycarbonyl).Peptide synthesis has transformed industries like medicine development and discovery. It makes it possible to create unique peptides that can be used to research the roles of proteins, create vaccines, and create novel treatments. The method has grown more accessible and efficient thanks to developments in automated peptide synthesizers and solid supports, spurring innovation in biotechnology and medicine.
