Catalytic-kinetic photometric determination of trace amounts of nitrite

Based on the catalytic effect of nitrite on the color fading, reaction of oxidation of rhodamine bypotassium bromate in dilute phosphoric acid solution, a catalytic kinetic photometric method fo the determination of trace amounts of nitrite was developed having its absorption maxima at 540nm. The molar absorptivity of the colour reaction was found to be 2.9×10~5 L·mol-1·cm-1, and beer's law was kept in the range of 0~6.5 ug/25 ml, of solution. The method has been applied to the determination of nitrite in several be fresh canned goods fruit and vegetable samples with satisfactory results.