title: Performance of a pentafluorophenylpropyl stationary phase for the electrospray ionization high-performance liquid chromatography-mass spectrometry-mass spectrometry assay of cocaine and its metabolite ecgonine methyl ester in human urine.
abstract: A pentafluorophenylpropyl (PFPP) bonded silica column has been used for the high-performance liquid chromatography-electrospray ionization-mass spectrometry-mass spectrometry assay (HPLC-ESI-MS-MS) of cocaine (COC) and its metabolite, ecgonine methyl ester (EME) in human urine. COC and EME were used as model basic solutes to demonstrate that a PFPP phase yields excellent results for the assay and validation of drugs in biological fluids. The assay was linear over three orders of magnitude (1.0-1000 ng/ml) and precision and accuracy of the assay was 4 and 15%, respectively. The limit of detection (LOD) for COC and EME was 1.6 and 2.8 pg on column, respectively. In addition, only a simple 1:10 dilution of the urine was necessary for the sample preparation procedure thus saving time on a laborious extraction step. The major advantage of the PFPP phase was the enhancement of the ESI-MS signal by providing good retention and good peak shape of COC and EME with a mobile phase of 90% acetonitrile. The MS signal for COC was a factor of 12 times greater on the PFPP phase than on the C18 phase.
authors.affiliation: Drug Metabolism Technology Group, Pfizer, Inc., Central Research Division, Groton, CT 06340, USA. shane_r_needham@groton.pfizer.com
authors.forename: S R
authors.initials: SR
authors.lastname: Needham
authors.forename: P M
authors.initials: PM
authors.lastname: Jeanville
authors.forename: P R
authors.initials: PR
authors.lastname: Brown
authors.forename: E S
authors.initials: ES
authors.lastname: Estape
mesh_terms: D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003042:Cocaine / Q000031:analogs & derivatives / Q000652:urine*; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D003042:Cocaine; C034524:ecgonine methyl ester