Determination of malonaldehyde in biological materials by high-pressure liquid chromatography.

An HPLC method is described for the determination of malonaldehyde in biological materials. The procedure involves extracting the sample with trichloracetic acid, heating the extract with thiobarbituric acid, separating the thiobarbituric acid-malonaldehyde complex on a mu Bondapak C18 column, and measuring the absorbance using a 546-nm interference filter. The method was found to be specific for malonaldehyde in several food and feed samples. Under routine assay conditions, a coefficient of variability of 7.0% was obtained for samples containing 1-2 microgram of malonaldehyde per gram (instrument detection limit 1 ng). This procedure yields lower values for the concentration of malonaldehyde in food samples than the conventional spectrophotometric procedure based on absorbance of the thiobarbituric acid-malonaldehyde complex at 532 nm.