Quantification of Total N-Nitrosamine Concentrations in Aqueous Samples via UV-Photolysis and Chemiluminescence Detection of Nitric Oxide
详细信息 查看全文
- 作者：Florian BreiderUrs von Gunten
- 刊名：Analytical Chemistry
- 出版年：2017
- 出版时间：February 7, 2017
- 年：2017
- 卷：89
- 期：3
- 页码：1574-1582
- 全文大小：430K
- ISSN：1520-6882
文摘
N-Nitrosamines are potent mutagens and carcinogens that can be formed during oxidative water treatment. This study describes a novel method for the determination of total N-nitrosamines by UV-photolysis and subsequent chemiluminescence detection of nitric oxide. Denitrosation of N-nitrosamines was accomplished with a microphotochemical reactor consisting of a knitted reaction coil and a low-pressure mercury lamp. The detection limits for differing N-nitrosamines ranged between 0.07 μM (14 pmol injected) and 0.13 μM (26 pmol injected). The nitric oxide formation from selected N-nitrosamines was linear (R2 = 0.98–0.99) from 0.1 to 10 μM. The small cross-section and volume of the microphotochemical reactor used in this study was optimal to reach a sensitivity level comparable to chemical denitrosation-based methods. In addition, this method had several advantages over other similar methods: (i) compared to chemical denitrosation with copper monochloride or triiodide, the UV-photolysis does not require chemicals and is not affected by interferences of byproducts (e.g., formation of NOI), (ii) the reproducibility of replicates was enhanced compared to the triiodide-based method, and (iii) a commercially available photoreactor and NO analyzer were used. The application of this method for the determination of the N-nitrosamine formation potential of personal care products demonstrates its utility for assessing whether N-nitrosodimethylamine (NDMA) or other specific nitrosamines of current interest are dominant or minor components, respectively, of the total N-nitrosamine pool in technical aquatic systems or biological samples.