Flow-injection analysis-spectrophotometric determination of nitrite and nitrate in water samples by reaction with proflavin.
A flow-injection manifold is proposed for determination of nitrite based on the reaction with 3,6-diamino acridine (proflavin sulfate) in hydrochloride acid medium. The assembly is adapted for nitrate determination by including a reductive column filled with copperized cadmium. The influence of foreign substances is also studied. The method gives a linear calibration graph over the range 0.06-4 mg 1(-1) nitrite, with an RSD <0.5%. The method was applied to nitrite and nitrate determinations in either waste water or coastal marine water samples.
Segarra Guerrero
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R
Departamento de Química Analitica, Universitat de Valéncia, Valéncia, Spain.
Goméz Benito
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C
Martínez Calatayud
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J