Takeda Kazuhiko, Nojima Hitoshi, Kuwahara Kengo, Chidya Russel Chrispine, Adesina Adeniyi Olufemi, Sakugawa Hiroshi
Graduate School of Biosphere Science, Hiroshima University.
Faculty of Integrated Arts and Sciences, Hiroshima University.
Anal Sci. 2018;34(4):459-464. doi: 10.2116/analsci.17P536.
A non-enzymatic fluorescence method for the determination of hydrogen peroxide (HO) was investigated. This method is based on the hydroxylation reaction of terephthalate (TP) by hydroxyl radical formed from reaction between HO and Fe(II), resulting in the formation of a strongly fluorescent 2-hydroxyterephthalate (HTP). Under optimized conditions, a 3 nM detection limit and 1.0% precision at 200 nM were obtained. This was sensitive enough to determine the concentrations of HO in coastal marine environments. The slopes of the calibration curve in seawater were nearly the same as those in Milli-Q water, suggesting that the fluorescent intensity was not affected by coexisting sea salts. However, the presence of nitrite at more than 10 μM interfered with the formation of HTP. The developed method was successfully applied to determine the concentrations of HO in Osaka Bay on the research vessel. The results obtained in Osaka Bay demonstrated that HO was photochemically produced via the photolysis of dissolved organic matter supplied from the river with fresh water at the surface layer.
研究了一种用于测定过氧化氢（HO）的非酶荧光法。该方法基于HO与Fe(II)反应生成的羟基自由基对苯二甲酸酯（TP）的羟基化反应，从而形成强荧光的2-羟基对苯二甲酸（HTP）。在优化条件下，检测限为3 nM，在200 nM时精密度为1.0%。该方法灵敏度足以测定沿海海洋环境中HO的浓度。海水中校准曲线的斜率与超纯水（Milli-Q水）中的斜率几乎相同，表明荧光强度不受共存海盐的影响。然而，亚硝酸盐浓度超过10 μM时会干扰HTP的形成。所开发的方法成功应用于研究船上对大阪湾HO浓度的测定。在大阪湾获得的结果表明，HO是通过表层河流淡水供应的溶解有机物的光解光化学产生的。
