title: Determination of caprolactam and 6-aminocaproic acid in human urine using hydrophilic interaction liquid chromatography-tandem mass spectrometry.
abstract: A simple and rapid assay based on hydrophilic interaction liquid chromatography with tandem mass spectrometry has been first developed and validated for simultaneous determination of caprolactam (CA) and 6-aminocaproic acid (6-ANCA) in human urine using 8-aminocaprylic acid as internal standard. A 20μL aliquot of urine was injected directly into the liquid chromatography tandem mass spectrometry (LC-MS-MS) system. The analytes were separated on a Phenomenex Luna HILIC column with gradient elution. Detection was performed on Triple Quadrupole LC-MS in positive ions multiple reaction monitoring mode using electrospray ionization. The calibration curves were linear (r(2)≥0.995) over the concentration range from 62.5 to 1250ng/mL for CA and 31.25 to 1000ng/mL for 6-ANCA. The detection limits of CA and 6-ANCA were 62.5 and 15.6ng/mL, respectively. The intra-day and inter-day precisions were within 8.7% and 9.9%, respectively. The intra-day and inter-day accuracy were between 5.3% and 3.5%, and between 6.1% and 6.6%, respectively. The method proved to be simple and time efficient, and was successfully applied to evaluate the kinetics of caprolactam in one unusual case of caprolactam poisoning.
authors.affiliation: Division of Clinical Toxicology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Ya-Hsueh
authors.initials: YH
authors.lastname: Wu
authors.forename: Ming-Ling
authors.initials: ML
authors.lastname: Wu
authors.forename: Chun-Chi
authors.initials: CC
authors.lastname: Lin
authors.forename: Wei-Lan
authors.initials: WL
authors.lastname: Chu
authors.forename: Chen-Chang
authors.initials: CC
authors.lastname: Yang
authors.forename: Robert Tate
authors.initials: RT
authors.lastname: Lin
authors.forename: Jou-Fang
authors.initials: JF
authors.lastname: Deng
mesh_terms: D000328:Adult; D015119:Aminocaproic Acid / Q000493:pharmacokinetics / Q000652:urine*; D002209:Caprolactam / Q000493:pharmacokinetics / Q000506:poisoning / Q000652:urine*; D002853:Chromatography, Liquid / Q000379:methods*; D002927:Cimetidine / Q000506:poisoning; D004347:Drug Interactions; D004355:Drug Stability; D005260:Female; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D016014:Linear Models; D015203:Reproducibility of Results; D012640:Seizures; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D002209:Caprolactam; D002927:Cimetidine; D015119:Aminocaproic Acid