solidphasepeptidisynteesillä

Solid-phase peptide synthesis, often abbreviated as SPPS, is a method for assembling a peptide chain on an insoluble polymeric support. This technique allows for the sequential addition of amino acids to a growing peptide chain, with each amino acid being attached to the resin before the next one is added. The key advantage of SPPS lies in its ability to simplify purification. After each coupling step, excess reagents and byproducts can be washed away by simply filtering the resin. This greatly reduces the complexity of purification compared to traditional solution-phase methods, which require purification after each step.

The process typically begins with the immobilization of the first amino acid, with its carboxyl group, onto a resin. This amino acid is usually protected at its amino group with a suitable protecting group, such as Fmoc (9-fluorenylmethyloxycarbonyl) or Boc (tert-butyloxycarbonyl). Following deprotection of the amino group, the next protected amino acid is activated and coupled to the free amino group on the resin-bound peptide chain. This cycle of deprotection and coupling is repeated until the desired peptide sequence is synthesized.

Once the synthesis is complete, the peptide is cleaved from the resin, and any remaining side-chain protecting groups are removed simultaneously, typically using strong acids like trifluoroacetic acid (TFA). The crude peptide is then purified, often by high-performance liquid chromatography (HPLC). SPPS has revolutionized peptide chemistry, enabling the efficient and relatively straightforward synthesis of peptides for research, diagnostics, and therapeutic applications.