A Spectrophotometric Microdetermination of Keto Acids with 3-Methyl-2-benzothiazolone Hydrazone

Abstract

Various keto acids react sensitively with 3-methyl-2-benzothiazolone hydrazone to form the azine derivatives, which give the characteristic ultraviolet absorption spectra. The effect of pH, temperature, reaction period, buffer and the concentration of the reagent on the reaction and the spectra were investigated. Optimal conditions for the microdeter-mination of keto acids were established. Microamounts of keto acids (0.02_??_0.3 or 0.4 μmole) were determined rapidly by this simple method with satisfactory results. Amino acids, fatty acids and most inorganic salts did not interfere with the determination of keto acids.