Spectrophotometric determination of a thiobarbituric acid-reactive substance in human hair

A simple and sensitive spectrophotometric method for the determination of a thiobarbituric acid-reactive substance (TBARS) in human hair has been developed. The proposed method is based on the formation of a red-colored product by the reaction of products of lipid peroxidation with thiobarbituric acid in an acidic medium. The absorbance of the resulting red product was measured at 534 nm. The linear dynamic range was between 1.0 and 20 micromol/L. The recoveries were 98.3-105.0%, and the relative standard deviations (RSD) were 0.32-1.24, respectively. TBARS in digested hair sample was stable for 3 days at room temperature. It was found that, using this method, the hair TBARS concentration in smokers (0.116 +/- 0.030 micromol/g, n = 30) was significantly higher than that in non-smokers (0.096 +/- 0.015 micromol/g, n = 30) (p < 0.05).