Colorimetric Determination of 4-Hydroxyaminoquinoline 1-Oxide and 4-Aminoquinoline 1-Oxide

Colorimetric methods for the estimation of 4-hydroxyaminoquinoline 1-oxide and 4-aminoquinoline 1-oxide have been developed. The former was estimated by a modification of Zucker and Nason's method (Zucker and Nason, 1955). The method for the estimation of 4-aminoquinoline 1-oxide is based on the formation of a stable hydroxyazo dye which is formed after coupling of diazotized 4-aminoquinoline 1-oxide with 2-hydroxy-6, 8-naphthalenedisulfonic acid in alkaline condition. The formation of 4-hydroxyaminoquinoline 1-oxide and 4-aminoquinoline 1-oxide in the course of microbial reduction of 4-nitroquinoline 1-oxide was studied by using the present methods.