Precolumn fluorescence derivatization of the antagonist [Arg(6),D-Trp(7.9),MePhe(8)]-substance P{6-11} with benzoin in high-performance liquid chromatography and selective detection of arginine-containing fragments in its degradation products

Precolumn fluorescence derivatization for the determination of the antagonist [Arg(6),D-Trp(7,9),MePhe(8)]-Substance P{6-11} (antagonist G) using benzoin in HPLC was studied. Under the conditions chosen (0.067 M NaOH, heating at 100 degrees C for 10 s), a good yield of fluorescent derivatives was obtained and no methodology-related degradation occurred. The detection limit of antagonist G was 0.21 nmol/ml. The method has been applied to the selective and sensitive detection of arginine-containing fragments in degradation products of antagonist G.