Creatinine measurements in 24 h urine by liquid chromatography-tandem mass spectrometry.
Park-EK; Watanabe-T; Gee-SJ; Schenker-MB; Hammock-BD
J Agric Food Chem 2008 Jan; 56(2):333-336
A simple, sensitive, and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determining urinary creatinine was developed and used to evaluate 24 h urine samples collected during an exposure study. Urine (1 microL) was diluted with methanol and then directly applied to LC-MS/MS. Under electrospray ionization (ESI) conditions, the transition molecules of creatinine and creatinine- d3 were observed at m/z 114 > 44 and m/z 117 > 47, respectively. The retention time of creatinine was 0.59 min. The linear range was 1-2000 ng/mL, with a detection limit in urine of 1 ng/mL. LC-MS/MS and colorimetric end-point methods were significantly associated (R2 = 0.8785, p < 0.0001). The LC-MS/MS method to determine creatinine in 24 h urine samples had shorter retention times, was more sensitive, reliable, reproducible, simple, selective, and used a smaller sample size than other LC-MS/MS or commercial methods.
Agricultural-chemicals; Chemical-composition; Chemical-hypersensitivity; Chemical-reactions; Urinalysis; Exposure-levels; Urine-chemistry; Sample-preparation; Sampling-methods
Department of Entomology and UCD Cancer Research Center, University of California, Davis, California 95616
Agriculture; Cooperative Agreement
Agriculture, Forestry and Fishing
Journal of Agricultural and Food Chemistry
University of California - Davis