Omkar B. Ijare1, Tom Blydt-Hansen2, Tedros Bezabeh1
1National Research Council Institute for Biodiagnostics, Winnipeg, Manitoba, Canada; 2Pediatric Nephrology, Children's Hospital, University of Manitoba, Winnipeg, Manitoba, Canada
Urine analysis by 1H NMR spectroscopy is widely used for the study of various disease processes. The chemical shifts of the key metabolites in urine such as citrate, creatinine, and trimethylamine N-oxide are pH-dependent, which can make reliable analysis of 1H NMR spectroscopic data difficult. Urine pH can vary over the range 4.6 - 8.0 under physiological stress. In the present study, we examined the effect of pH on the chemical shifts of above metabolites and found that adjusting the pH of urine to 7.1 0.2 is essential for the reliable classification of 1H NMR spectroscopic data of urine in biomedical applications.