Analysis of N -nitrosodiethylamine by ion chromatography coupled with UV photolysis pretreatment

Nitrosamines such as N-nitrosodiethylamine (NDEA) are commonly detected by spectrophotometry after photolysis and Griess reaction (PG) in food industries for lower cost. Results of this research indicate that NDEA decays rapidly under UV irradiation, and concentrations of the generated NO2- and NO3- ions vary with photolysis conditions. Thus, the measurement of the PG method may be inconsistent because it is based on the amount of photoproduced NO2-. In addition, more errors may be present in the PG method since NO3- cannot be measured colorimetrically using Griess reagent. In this work, the sum of the concentrations of photoproduced NO2- and NO3- was found to be equivalent to the initial NDEA before photolysis, and a photolysis-ion chromatography method was validated, which may serve as a feasible and accurate method to determine nitrosamines.