Urinalysis - The Carter Center

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4. A blue to green color indicates a positive reaction.
5. Report as positive or negative.
Prparation of Fouchet's Reagent (See Reagent Number 9 )
B. Barium chloride Filter Paper Method
It is the modification of Harrison's test. The barium chloride is supplied
on thick filter paper that has been soaked in a saturated solution of
barium chloride.
Principle
The principle of the test is the same as Harrison's (Fouchet's) Test.
Procedure
1. Hold a strip of barium chloride paper perpendicularly in the urine
for a few seconds
2. Place one or two drops of Fouchet's Reagent on the saturated
area.
3. Look for the appearance of a green color, which constitutes a
positive reaction.
4. Report as positive (formation of a green color) or negative
(formation of any color except green, or no color formation).
Preparation of Barium Chloride Filter Paper( See Reagent Number 3)
Sensitivity
Harrison's Test is so sensitive that it detects as small as 0.1 - 0.2 mg of
bilirubin in 100ml of urine.
C. Diazotization Tests for Bilirubin
The tablet and reagent strip tests for bilirubin are based on the coupling
of bilirubin with a diazonium salt in an acid medium to form azobilirubin,
which gives a blue or purple color.