Determination of a cyclic heptapeptide, a novel fibrinogen receptor antagonist, in human plasma by high-performance liquid chromatography with automated pre-column derivatization, column switching and fluorescence detection
Kline, W.F.; Matuszewski, B.K.; Hsieh, J.Y.
Journal of Chromatography 578(1): 31-37
ISSN/ISBN: 0021-9673 PMID: 1328269 Accession: 007192402
A sensitive high-performance liquid chromatographic (HPLC) assay for the determination of the cyclic heptapeptide Ac-Cs-Asn-Dtc-Amf-Gly-Asp-Cys-OH (Dtc = .beta.,.beta.-dimethylthioproline, and Amf = p-aminomethylphenylalanine) in human plasma has been developed. The key steps in the assay include: solid-phase extraction of the drug from plasma, chemical derivatization of the primary amino group with naphthalene-2,3-dicarboxyaldehyde in the presence of N-acetyl-D-penicillamine as a nucleophile to form a fluorescent benzo[f]isoindole derivative, and HPLC with column switching to provide the necessary chromatographic separation of the derivative from endogeneous plasma components. The assay has been validated in the concentration range 1-10 ng/ml of plasma.