Urinalysis and Body Fluids 6th Edition by Majorie DiLorenzo, Susan Strasinger

Exercise 74

The reagent strip test for nitrite uses the:

A. Greiss reaction

B. Ehrlich reaction

C. Peroxidase reaction

D. Pseudoperoxidase reaction

Step 1 of 2

Nitrite reagent strip test:

Nitrate is the normal component of urine which is reduced to nitrite.

• Nitrite is not normally present in urine.

• The test is to detect capability of some bacteria to reduce nitrate to nitrite.

• Greiss reaction is used to analyze the existence of nitrite in urine.

o Nitrite reacts with para-arsanilic acid or sulfanilamide (aromatic amine) to give diazonium salt.

o The diazonium salt reacts with tetrahydrobenzoquinolin to give azodye (pink color).

o Shades of pink color indicate the presence of some quantity of bacteria in urine.

Therefore, “Greiss reaction” is used to detect nitrite in reagent strip. Hence, the correct answer is option.