Validation of an HPLC-MS-MS method for the determination of urinary s-benzylmercapturic acid and s-phenylmercapturic acid.
J Chromatogr Sci 2011 Aug; 49(7):547-553
A high-performance liquid chromatography-tandem mass spectrometric (HPLC-MS-MS) method is presented and evaluated for the determination of S-benzylmercapturic acid (S-BMA) and S-phenylmercapturic acid (S-PMA) in human urine. Both of these compounds are important for occupational health owing to their use as biomarkers of exposure to toluene and benzene, respectively. Toluene is used extensively as a solvent, and the health hazards of benzene have been well established. The optimized urine sample preparation scheme consists of solid-phase extraction (SPE) followed by an acetone wash. The chromatographic analysis consists of a reversed-phase gradient system, which uses electrospray ionization in negative-ion mode with a triple-quadrupole mass spectrometric detector. Accuracy and precision of this method are demonstrated by a series of recovery studies of spiked human urine and synthetic urine substitute. Spike levels at 1, 2, 6, 8, and 30 ng/mL for both analytes demonstrate average recoveries (accuracy) ranging from 99 to 110 percent. Precision as measured by the relative standard deviation (percentRSD) of multiple samples (n = 9) at each concentration level was 5.3 percent or less for both analytes in urine. The limit of detection (LOD) is approximately 0.2 ng/mL for S-BMA and S-PMA. This data, other figures of merit and other factors, such as ion suppression of the electrospray ionization source, are discussed.
Analytical-instruments; Analytical-processes; Laboratory-techniques; Liquid-chromatography; Mass-spectrometry; Urinalysis; Urine-chemistry; Acids; Mercaptans; Phenyls; Biomarkers; Toluenes; Benzenes; Sample-preparation; Sampling; Sampling-equipment; Sampling-methods; Solvents; Electrochemical-analysis; Ionization; Metabolites
Clayton B'Hymer, National Institute for Occupational Safety and Health, Division of Applied Research and Technology, Mail Stop C-23, 4676 Columbia Parkway, Cincinnati, OH 45226, USA
Healthcare and Social Assistance; Services; Manufacturing
Journal of Chromatographic Science