[Gas liquid chromatographic determination of tricarbonic cycle acids in human plasma]

A procedure is proposed to identify non-volatile organic acids in small human plasma volumes by gas liquid chromatography (GLC), which shows a high degree of acid separation with the rather simplified preparation of samples. The principle of the procedure is deproteination, simultaneous perchloric acid neutralization, plasma lipid hydrolysis, transformation of the salts of carboxylic acids to free acids, and acid methylation. Acid GLC is performed on a gas chromatograph with a flame ionization detector, by using a 25-m x 0.2-mm column. The peaks are identified, by correlating the retention times for reference and plasma acids. Lactate, pyruvate, fumarate, malate, alpha-ketoglutarate, citrate, and isocitrate have been identified in the plasma samples.