Procedure 1 mLBial’s reagent + 1 mL test solution boil gently until bubbles are observed *Blue green color : +
Introduction TAUBER’S BENZIDINE TEST -> more specific for pentoses -> can detect up to 0.01 mg of the pentose either in its free of combined form
Procedure 0.5 mLTauber’s reagent 5 drops of test solution boil over an open flame for 1-2 minutes *formation of cherry red solution : +
Discussion It is more specific for pentoses than the bial’s test because it can detect as little as 0.01 mg of a pentose. The presence of a high concentration of hexoses does not interfere with the test. A positive test is indicated by the formation of a cherry red color.
Application When testing for pentose in urine, the urine (0.1 cc.) and benzidinesolution (0.5 cc.) is brought to vigorous boiling. The mixtureis cooled under tap water and 1 cc. of distilled water is added.In the presence of pentose a pink to red color is shown immediately,whereas if pentose is absent the mixture has a yellowish browncolor. Pentu