title: Determination of eptifibatide concentration in human plasma utilizing the liquid chromatography-tandem mass spectrometry method.
abstract: A sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to determine the concentration of eptifibatide in human plasma. Following protein precipitation, the analyte was separated on a reversed-phase C(18) column. Acetonitrile:5mM ammonium acetate:acetic acid (30:70:0.1, v/v/v) was used at a flow-rate of 0.5mL/min with the isocratic mobile phase. An API 4000 tandem mass spectrometer equipped with a Turbo IonSpray ionization source was used as the detector and was operated in the positive ion mode. "Truncated" multiple reaction monitoring using the transition of m/z 832.6-->m/z 832.6 and m/z 931.3-->m/z 931.3 was performed to quantify eptifibatide and the internal standard (EPM-05), respectively. The method had a lower limit of quantification of 4.61ng/mL for eptifibatide. The calibration curve was demonstrated to be linear over the concentration range of 4.61-2770ng/mL. The intra- and inter-day precisions were less than 10.5% for each QC level, and the inter-day relative errors were 2.0%, 5.6%, and 2.8% for 9.22, 184, and 2490ng/mL, respectively. The validated method was successfully applied to the quantification of eptifibatide concentration in human plasma after intravenous (i.v.) administration of a 270-microg/kg bolus of eptifibatide and i.v. administration of eptifibatide at a constant rate of infusion of 2microg/(kgmin) for 18h in order to evaluate the pharmacokinetics.
authors.affiliation: Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 646 Songtao Road, Shanghai 201203, PR China.
authors.forename: Jia
authors.initials: J
authors.lastname: Liu
authors.forename: Xiaotao
authors.initials: X
authors.lastname: Duan
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Chen
authors.forename: Dafang
authors.initials: D
authors.lastname: Zhong
mesh_terms: D002138:Calibration; D002853:Chromatography, Liquid / Q000379:methods*; D004355:Drug Stability; D000077542:Eptifibatide; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D010455:Peptides / Q000097:blood* / Q000737:chemistry; D010975:Platelet Aggregation Inhibitors / Q000097:blood / Q000737:chemistry; D012015:Reference Standards; D015203:Reproducibility of Results; D013997:Time Factors
chemical_list: D010455:Peptides; D010975:Platelet Aggregation Inhibitors; D000077542:Eptifibatide