Shang Li, Zhang Lihua, Dong Shaojun
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Graduate School of the Chinese Academy of Sciences, Chinese Academy of Sciences, Changchun, 130022, China.
Analyst. 2009 Jan;134(1):107-13. doi: 10.1039/b812458b. Epub 2008 Oct 20.
A new fluorescent sensor for the sensitive and selective detection of cyanide (CN(-)) in aqueous media was developed herein. The sensing approach is based on CN(-)-modulated quenching behavior of Cu(2+) toward the photoluminescence (PL) of CdTe quantum dots (QDs). In the presence of CN(-), the PL of QDs that have been quenched by Cu(2+) was found to be efficiently recovered, which then allows the detection of CN(-) in a very simple approach. Experimental results showed that the pH of the buffer solution, concentration of copper ions, and size of CdTe QDs all influenced the response of the sensor to CN(-). Under the optimal conditions, a good linear relationship between the PL intensity and the concentration of CN(-) can be obtained in the range of 3.0 x 10(-7) to 1.2 x 10(-5) M, with a detection limit as low as 1.5 x 10(-7) M. In addition, the present fluorescent sensor possesses remarkable selectivity for cyanide over other anions, and negligible influences were observed on the cyanide detection by the coexistence of other anions or biological species (such as albumin and typical blood constituents). Therefore, we expect the proposed copper ion-modified QDs to be an efficient and reliable sensing system to monitor cyanide concentration in environmental or clinical applications.
本文开发了一种用于在水性介质中灵敏且选择性地检测氰化物（CN⁻）的新型荧光传感器。该传感方法基于CN⁻对Cu²⁺猝灭碲化镉量子点（QDs）光致发光（PL）的调制行为。在存在CN⁻的情况下，发现已被Cu²⁺猝灭的QDs的PL能有效恢复，从而可以通过非常简单的方法检测CN⁻。实验结果表明，缓冲溶液的pH值、铜离子浓度和碲化镉量子点的尺寸均会影响该传感器对CN⁻的响应。在最佳条件下，PL强度与CN⁻浓度在3.0×10⁻⁷至1.2×10⁻⁵ M范围内可获得良好的线性关系，检测限低至1.5×10⁻⁷ M。此外，这种新型荧光传感器对氰化物具有相对于其他阴离子的显著选择性，并且其他阴离子或生物物种（如白蛋白和典型血液成分）的共存对氰化物检测的影响可忽略不计。因此，我们期望所提出的铜离子修饰的量子点在环境或临床应用中成为监测氰化物浓度的高效且可靠的传感系统。
