Validation of an alternative method for total nitrogen analysis in water samples

Abstract

The current study presents the analytical validation method and performance characteristics of visible molecular adsorption spectrophotometry in determining the nitrogen concentration in water samples after the catalytic oxidation under controlled temperature and pressure conditions, using potassium peroxodisulfate, according to Romanian standard SR EN ISO 11905-1:2003. The quality of the calibration range (the determination coefficient of the calibration curve, the linearity and homogenity tests), the limit of detection, the limit of quantification, selectivity, robustness, recovery tests and the uncertainty calculation of the method allow the successful use of the method, using the specific conditions imposed by the analytical standard method.