title: Simultaneous extraction and quantitation of fentanyl and norfentanyl from primate plasma with LC/MS detection.
abstract: The quantitation of both fentanyl and its desalkyl metabolite, norfentanyl, in plasma using LC/MS has not been previously described. The detection and quantitation of fentanyl and norfentanyl was achieved using LC/MS detection. The liquid-liquid extraction used toluene as the organic phase. Chromatography was carried out using a Zirchrom-PBD (50 mm x 2.1 mm, 3 microm) column with a mobile phase of acetonitrile-ammonium acetate (10 mM), citrate (0.1 mM, pH 4.4) (45:55, v/v) with a flow rate of 0.3 ml/min. Mass spectroscopy detection was performed using ESI in the positive mode. The LOQ for fentanyl was 25 pg/ml and norfentanyl was 50 pg/ml. For the concentrations of 75, 250, and 750 pg/ml, respectively, fentanyl had inter-day precisions of 6.6, 7.2, and 6.6% with accuracies of 4.0, 5.1, and 5.1% and intra-day precisions of 1.6, 1.9, and 1.9% with accuracies of 11.6, 9.4, and 8.4%, and norfentanyl had inter-day precisions of 7.4, 0.3, and 0.7% with accuracies of 9.1, 8.8, and 12.3% and intra-day precisions of 5.3, 1.4, and 0.1% with accuracies of 10.9, 8.9, and 12.8%. The recoveries of fentanyl were 85, 92, and 75% and of norfentanyl were 40, 49, and 46% at the 75, 250, and 750 pg/ml concentrations, respectively.
authors.affiliation: Department of Anatomy and Physiology, Zoological Pharmacology Laboratory, College of Veterinary Medicine, 129 Coles Hall, Kansas State University, Manhattan, KS 66506-5802, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Koch
authors.forename: R
authors.initials: R
authors.lastname: Isaza
authors.forename: J W
authors.initials: JW
authors.lastname: Carpenter
authors.forename: R P
authors.initials: RP
authors.lastname: Hunter
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods; D005283:Fentanyl / Q000031:analogs & derivatives* / Q000097:blood* / Q000737:chemistry / Q000302:isolation & purification*; D013058:Mass Spectrometry / Q000379:methods; D011323:Primates
chemical_list: C080127:norfentanyl; D005283:Fentanyl