Gas Chromatography-Mass Spectrometry of Chemically Modified Amino Acids in Silk and Wool Fibers Treated With Epichlorohydrin, Glycidol and Glycidyl Methacrylate

Abstract

Chemically modified amino acids in the silk and wool fibers treated with epichlorohydrin (E), glycidol (G) and glycidyl methacrylate (GMA), were identified by gas chromatography-mass spectrometry as their N(O )-trifluoroacetyl n-butyl ester derivatives. 0-(Dihydroxypropyl)-and O-(chlorohydroxypropyl)tyrosines, and N`-(dihydroxypropyl)-and N`,N`-bis(dihydroxypropyl)lysines were identified in all silk and wool samples, indicating that OH and Cl groups of the epoxide-amino acid adducts were labile during acid hydrolysis of the samples. N',N'-B is (chlorohydroxy pro pyl) lysine and O-[(dihydroxypropoxy)hydroxypropyl] tyrosine were also identified in the silk and wool fibers treated with G, the latter being formed by addition of a second molecule of G to O-(dihydroxypropyl) tyrosine residue. S (Dihydroxypropyl)-and S-(2-carboxypropyl) cysteines were identified by the single ion monitoring (SIM) method for the wool fibers treated with GMA, indicating that thiol groups of cysteine residues could react with both epoxy and methacryl groups of GMA. S-(Chlorohydroxypropyl) cysteine as well as S (dihydroxypropyl) cysteine were found in the other wool samples by the SIM method. N`-(Chlorohydroxypropyl)-and N`,N`-b is (chlorohy droxypro pyl) ly sines were also found in the wool fibers treated with E by the SIM method.