DETERMINATION OF PEPTIDE-520 IN HUMAN PLASMA USING POSTCOLUMN PHOTOLYSIS WITH ELECTROCHEMICAL DETECTION IN LIQUID-CHROMATOGRAPHY

A simple LC method for the determination of peptide 520 in human plasm a was developed. Based on micellar chromatography, sodium octyl sulpha te (SOS) was added into the mobile phase in order to separate the pept ide from human plasma components. The procedure was fast and sensitive for the determination of the peptide in untreated human plasma. The e lectrochemical (EC) detection limit for peptide 520 in human plasma wa s 0.5 mug ml-1. Linearity of the calibration plot for peptide 520 in h uman plasma was 0.999. This approach represents a direct injection tec hnique for the potential detection and analysis of numerous peptides i n biofluids, besides just plasma, with absolute quantification.