摘要 |
Ascorbic acid or dehydroascorbic acid is determined by reaction with a tetrazolium salt selected from 3-(4,5-dimethyl-thiazolyl-2)-2,5-diphenyl-tetrazolium bromide, nitrotetrazolium blue, tetrazolium blue chloride and distyryl-nitro blue tetrazolium chloride, in the presence of phenazine methosulphate and a detergent, at a weakly acidic pH value, and evaluating the coloration obtained as a measure of the initial acid content. The method is particularly efficacious in substantially eliminating disturbance of the reaction by foreign substances. |