DISULFIDE LINKAGE TO POLYACRYLIC RESIN FOR AUTOMATED FMOC PEPTIDE-SYNTHESIS - IMMUNOCHEMICAL APPLICATIONS OF PEPTIDE RESINS AND MERCAPTOAMIDE PEPTIDES

The use of disulfide bonds for peptide-resin linkage in solid-phase pe ptide synthesis was investigated using polyacrylic polymers (Expansin( TM)) and automated Fmoc methodology. The disulfide moiety was bound to the support either by coupling a protected bifunctional handle or by an original stepwise procedure. Among the three different disulfide ha ndles that were investigated, only the aminoethyldithio-2-isobutyric a cid (AEDI) handle was stable enough to achieve peptide synthesis. A se ries of peptides of up to 10-20 amino acids were prepared in this mann er, in good yield and purity. Rapid and quantitative peptide release w as obtained by reduction with equimolecular amounts of dithiothreitol at pH 9 or tris(2-carboxymethyl) phosphine at pH 4.5. This allowed dir ect and rapid coupling of the released cysteamide peptides to an activ ated protein carrier and the use of free or resin-bound forms of the a ntigen in immunoassays. (C) Munksgaard 1993.