The micro-estimation of benzoic and hippuric acids in biological material

Abstract

The method applies to samples containing 0.05-10 mg. of these acids. It is based on the nitration of these acids at room temp., extraction of the resulting mononitro compounds, reduction to the corresponding amino compounds, followed by diazotization and finally coupling of the diazo compounds with a dye-forming base in acid soln. The amt. of dye is closely proportional to the amt. of benzoic or hippuric acid in the sample. The application of the method to tissues, blood and urine is described.