Electrochemical detection of oligopeptides through the precolumn formation of biuret complexes.
The relatively slow kinetics of formation of the electroactive Cu(II)-peptide complexes from larger (greater than 6 amino acids) peptides requires relatively high temperature and long reaction times for a postcolumn reactor. The precolumn incubation of bradykinin, Tyr8-bradykinin and insulin A chain with biuret reagent for 20 min at 60 degrees C leads to the formation of biuret complexes which can be subjected to chromatography in acidic or basic eluents. These complexes are detected electrochemically with a sensitivity similar to the Cu(II)-(ala)3 complex (1 nC/pmol at 1.0 ml/min). The influence of the column-packing material on the electrochemical detector response of the Cu-peptide complexes has also been studied.
Tsai
H Y
HY
Department of Chemistry, University of Pittsburgh, PA 15260.
Weber
S G
SG
D001737:Biuret; D001920:Bradykinin / Q000031:analogs & derivatives / Q000032:analysis; D002070:Butadienes; D002853:Chromatography, Liquid; D003300:Copper; D020724:Elastomers; D004563:Electrochemistry; D007328:Insulin / Q000032:analysis; D009842:Oligopeptides / Q000032:analysis*; D011108:Polymers; D013696:Temperature; D013997:Time Factors
D002070:Butadienes; D020724:Elastomers; D007328:Insulin; D009842:Oligopeptides; D011108:Polymers; C026201:bradykinin, Tyr-; D003300:Copper; D001737:Biuret; C028834:polybutadiene; D001920:Bradykinin