1988 Volume 4 Issue 2 Pages 207-210
Lipid peroxides in tissues were fluorometrically determined using 1, 3-diphenyl-2-thiobarbituric acid (DPTBA) as a fluorogenic reagent, and the results were compared with those obtained by the DPTBA-visible method, thiobarbituric acid (TBA)-fluorescence method, or TBA-visible method. The optimum conditions for determining lipid peroxides were analyzed by using brain homogenate. The optimum pH for the reaction of brain homogenate with DPTBA was 2.5. The amount of DPTBA suitable for the reaction with 100μl of a 1% brain homogenate was 0.12M. A linear relationship was observed between the fluorescence intensity and the amount of malondialdehyde (MDA) in the range of 1.25-12.5nmol/ml. The detection limit of the DPTBA-fluorescence method was 0.006nmol/g wet weight at a signal-to-noise ratio of 3. The sensitivity of this method was 5.5 times higher than that of the TBA-fluorescence method, lipid peroxides in tissues could be easily determined without separation from glucose and bilirubin which interfere with TBA method. Lipid peroxides could be determined more accurately, precisely, and quickly using a smaller amount of liver, heart and brain homogenates by the DPTBA-fluorescence method than by other methods.