Kodamatani Hitoshi, Kubo Shotaro, Takeuchi Akinori, Kanzaki Ryo, Tomiyasu Takashi
Division of Earth and Environmental Science, Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065, Japan.
Health and Environmental Risk Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan.
Environ Sci Technol. 2023 Apr 11;57(14):5924-5933. doi: 10.1021/acs.est.3c00273. Epub 2023 Mar 27.
Sensitive detection methods for nitrite (NO) and nitrate (NO) ions are essential to understand the nitrogen cycle and for environmental protection and public health. Herein, we report a detection method that combines ion-chromatographic separation of NO and NO, on-line photochemical conversion of these ions to peroxynitrite (ONOO) by irradiation with a 222 nm excimer lamp, and chemiluminescence from the reaction between luminol and ONOO. The detection limits for NO and NO were 0.01 and 0.03 μM, respectively, with linear ranges of 0.010-2.0 and 0.10-3.0 μM, respectively, at an injection volume of 1 μL. The results obtained by the proposed method for seawater analysis corresponded with those of a reference method (AutoAnalyzer based on the Griess reaction). As luminol chemiluminescence can measure ONOO at picomolar concentrations, our method is expected to be able to detect NO and NO at picomolar concentrations owing to the high conversion ratio to ONOO (>60%), assuming that contamination and background chemiluminescence issues can be resolved. This method has the potential to emerge as an innovative technology for NO and NO detection in various samples.
亚硝酸盐（NO）和硝酸盐（NO）离子的灵敏检测方法对于理解氮循环以及环境保护和公众健康至关重要。在此，我们报告一种检测方法，该方法结合了NO和NO的离子色谱分离、通过222 nm准分子灯照射将这些离子在线光化学转化为过氧亚硝酸盐（ONOO）以及鲁米诺与ONOO之间反应产生的化学发光。在进样体积为1 μL时，NO和NO的检测限分别为0.01和0.03 μM，线性范围分别为0.010 - 2.0和0.10 - 3.0 μM。所提出的海水分析方法得到的结果与参考方法（基于格里斯反应的自动分析仪）的结果一致。由于鲁米诺化学发光能够检测皮摩尔浓度的ONOO，假设污染和背景化学发光问题能够得到解决，基于向ONOO的高转化率（>60%），我们的方法有望能够检测皮摩尔浓度的NO和NO。该方法有潜力成为用于各种样品中NO和NO检测的创新技术。
