A revised method for nitrate analysis at low concentrations

A low-toxicity method is described for the analysis of low concentrations of nitrate nitrogen (NO3-N) using columns of Devarda’s Alloy in a matrix of fused alumina anti-bumping granules. The method was developed to solve logistical problems inherent in the use of cadmium-based methodologies in a developing nation and compared favourably with the accepted method of Havilah E. J., Wallis D. M., Morris R. and Woolnough J. A. (1977) A micro-colorimetric method for determination of ammonia in Kjeldahl digests with a manual spectrophotometer. Lab. Pract. 26, 545–547 which utilises spongy cadmium as a reagent.