Fluorimetric determination of nitrite in water using a novel fluorescent dye

A simple, sensitive and selective fluorimetric method for the determination of trace amounts of nitrite in different water samples (e.g., underground water, geothermal waste water, domestic waste water and drinking water) was proposed. The fluorimetric determination is based on the diazotization reaction of nitrite with a fluorescent dye, tetraamino zinc (II) phthalocyanine in an acidic medium. Under the optimum experimental conditions, nitrite can be determined in the range 10− 6–10− 4 mol·L− 1 with the detection limit 2.04 × 10− 8 mol·L− 1. The proposed method has been successfully applied to the determination of nitrite in various water samples. The results compared favorably with the results from a standard ISO certified method.