Department of Analytical Chemistry, College of Chemistry, Jilin University, Changchun, 130012, China.
Anal Bioanal Chem. 2014 Jan;406(3):879-86. doi: 10.1007/s00216-013-7490-0. Epub 2013 Dec 7.
In the present work, a novel flow-injection chemiluminescence method based on CdTe quantum dots (QDs) was developed for the determination of nitrite. Weak chemiluminescence (CL) signals were observed from a CdTe QDs-H2O2 system under basic conditions. The addition of a trace amount of hemoglobin (Hb) caused the CL from the CdTe QDs-H2O2 system to increase substantially. In the presence of nitrite, the ferrous Hb reacted with the nitrate to form ferric Hb and NO. The NO then bound to ferrous Hb to generate iron nitrosyl Hb. As a result, the CL signal from the CdTe QDs-H2O2-Hb system was quenched. Thus, a flow-injection CL analytical system for the determination of trace nitrite was established. Under optimum conditions, there was a good linear relationship between CL intensity and the concentration of nitrite in the range 1.0 × 10(-9) to 8.0 × 10(-7) mol L(-1) (R (2) = 0.9957). The limit of detection for nitrite using this system was 3.0 × 10(-10) mol L(-1) (S/N = 3). This method was successfully applied to detect nitrite in water samples.
在本工作中，基于 CdTe 量子点（QDs）开发了一种新的流动注射化学发光法，用于测定亚硝酸盐。在碱性条件下，从 CdTe QDs-H2O2 体系中观察到微弱的化学发光（CL）信号。加入痕量的血红蛋白（Hb）会导致 CdTe QDs-H2O2 体系的 CL 信号大幅增加。在存在亚硝酸盐的情况下，亚铁血红蛋白与硝酸盐反应生成高铁血红蛋白和 NO。然后，NO 与亚铁血红蛋白结合生成亚硝基铁血红蛋白。结果，CdTe QDs-H2O2-Hb 体系的 CL 信号被猝灭。因此，建立了一种用于测定痕量亚硝酸盐的流动注射 CL 分析系统。在最佳条件下，CL 强度与亚硝酸盐浓度在 1.0×10(-9)至 8.0×10(-7) mol L(-1)范围内呈良好的线性关系（R (2) = 0.9957）。该系统测定亚硝酸盐的检出限为 3.0×10(-10) mol L(-1)（S/N = 3）。该方法成功应用于水样中亚硝酸盐的测定。
