Bioanalysis of plasma acetate levels without derivatization by LC–MS/MS

The acetate ion has important physiological functions and important therapeutic applications. A rapid LC–MS/MS method is described to measure acetate ions in human plasma without chemical derivatization. A 200 μl sample was spiked with the internal standard 1,2- C-acetate and proteins precipitated with trichloroacetic acid. The supernatant was recovered and separated under acidic conditions on a C18-column. The eluent was alkalinized by post-column infusion of methanolic ammonium hydroxide. Acetate ions were monitored on a low resolution mass spectrometer in negative ion mode. Method was validated for accuracy and precision with a lower limit of quantitation of 9.7 μM and linear dynamic range up to 339.6 μM. The method is open for analytical improvement and adapts with metabolomic and pharmacometabolomic studies on chemicals of similar nature. Recent scientific investigation has been uncovering fascinating physiological functions of the acetate ion in the body that go beyond its conventional perception as a metabolite and promise utility as a therapeutic agent in many pathologic conditions. The expanding interest in the acetate ion underscore the compelling need for a bioanalytical method that offers rapid analysis without chemical derivatization of its levels in biological samples, applies minimal manipulation to the sample, allows high-throughput analysis, and adapts easily with common metabolomic and pharmacometabolomic investigations. Such method is important in analyzing experimental, preclinical, clinical and forensic samples. The present investigation discloses an LC–MS/MS method for the analysis of acetate in human plasma to corroborate methodologies already listed in the biomedical literature.