饮用水中亚硝酸盐高通量检测微孔板法的研究
Detection of nitritein in drinking water by high-throughput microplate method
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摘要: 亚硝酸盐与间苯二胺在强酸性条件下发生重氮化偶联反应,生成橙红色偶联产物环偶氮亚氨基苯。本研究基于该原理,以微孔板为载体,确定最佳测定波长,通过单因素实验、正交实验优化工作条件,建立一种高通量检测饮用水中亚硝酸盐含量的方法。结果表明,最佳测定波长为451 nm,最佳工作条件:盐酸浓度为0.4 mol/L、间苯二胺浓度为30 g/L、反应时间为10 min。该方法的检出限为0.017 mg/L,线性范围为0~5 mg/L,线性相关系数r为0.9997,空白加标回收率在95.24%~103.98%之间,变异系数小于5%。该方法快速、灵敏,抗干扰能力强,操作简便,可进行高通量筛选,用于饮用水等食品样品中亚硝酸盐残留量的定量测定。Abstract: Under strong acid conditions,diazo-coupling reactions between nitrite and m-phenylenediamine generate dzoic compound,which is an orange-red compound. Based on this principle,a high-throughput microplate method was established using microplate as the reaction vessel. To improve the sensitivity of this method,several experimental parameters were optimized. The results revealed that the optimum measurement wavelength was 451 nm,and using 30 g/L m-phenylenediamine(0.4 mol/L hydrochloric acid as the solvent)as the chromogenic agent,the reaction was complete within 10 min at room temperature. The detection limit was 0.017 mg/L,and linear range was 0~5 mg/L,with correlation coefficient value of 0.9997. Recoveries of nitrite from watsons distilled water were tested from 95.24% to 103.98%,with the coefficient of variation(CV)below 5%.This method was rapid,sensitive,easy to operate,and showed outstanding anti-interference ability,which was suitable for the screening of nitrite for a large number of drinking water samples.