Simultaneous determination of creatinine and acetate by capillary electrophoresis with contactless conductivity detector as a feasible approach for urinary tract infection diagnosis

Urinary tract infection (UTI) is one of the most common bacterial infection in human but its diagnosis is difficult. Metabolomic studies with nuclear magnetic resonance of urine have shown that acetic acid/creatinine ratio may be used for early UTI diagnosis. Here, a method for simultaneous determination of acetate and creatinine by capillary zone electrophoresis with contactless conductivity detector was developed for the first time. The separation was with 40 mM MES and 20 mM L-histidine as a background solution. The total time of a single run, including capillary conditioning, was less than 12 min. The method was successfully demonstrated for analysis of actual and fortified human urine samples after methanol dilution. Analytical figures of merit such as linearity, LOQ, and repeatability (intraday and interday) were studied.