31.2.1.2 Reagents
(a) 33% v/v aqueous solution of acetic acid.
(b) 10% aqueous solution of BaCl 2.
(c) Fouchet’s reagent: Dissolve 5 g TCA in about 60 ml of distilled water and
add to it 10 ml of 10% FeCl 3 solution, mix, and make thefinal volume
100 ml with distilled water.
31.2.1.3 Procedure
Acidify urine sample with few drops of 33% acetic acid. To 10 ml of acidified urine
sample, add 5 ml of 10% BaCl 2 solution. Mix well, and the precipitate isfiltered
through Whatman No. 1filter paper. Dry the precipitates in between two layers of
filter paper. Unfold thefilter paper and add one or two drops of Fouchet’s reagent on
the precipitates and observe the color produced. Green-blue color formed on the
precipitate indicates bile pigments in the urine.
Fig. 31.1 Bilirubin
metabolism
124 31 Qualitative Test for Bile Pigments and Urobilinogen in Urine