Institute of Polymer Materials, School of Materials Science and Engineering, Jiangsu University, Zhenjiang, China.
Zhenjiang Food and Drug Supervision and Inspection Center, Zhenjiang, China.
J Sep Sci. 2018 Dec;41(23):4394-4401. doi: 10.1002/jssc.201800866. Epub 2018 Nov 2.
Sulfadiazine is an environmental pollutant derived from abuse of antibiotics. Its content in environmental water is closely related to human health. Thus, a novel dual-emission surface molecularly imprinted nanosensor is designed for the specific adsorption and detection of sulfadiazine. In the system, blue emissive carbon quantum dots wrapped with silica served as the internal reference signal for eliminating background interference, while red emissive thioglycolic acid modified CdTe quantum dots (CdTe QDs), which are low dimensional semiconductor materials by the combination of cadmium and tellurium with excellent optical properties, were encapsulated in the imprinted layer to offer recognition signal. The fluorescence of CdTe quantum dots was quenched and the fluorescence quenching degree of carbon quantum dots was inconspicuous with the increase of concentration of sulfadiazine, thereby reflecting the color change. The detection of sulfadiazine was successfully achieved in a concentration range of 0.25-20 μmol/L with detection limit of 0.042 μmol/L and nanosensors had specific recognition for sulfadiazine over its analogues. Compared to single-emission fluorescence sensors, ratiometric fluorescence nanosensors had wider linear range and higher detection accuracy. Furthermore, the nanosensors were also successfully applied for the determination of sulfadiazine in real water and milk samples with acceptable recoveries. The study provides a feasible method for the detection of sulfadiazine and a reference for the detection of sulfonamides.
磺胺嘧啶是一种来源于抗生素滥用的环境污染物，其在环境水中的含量与人类健康密切相关。因此，设计了一种新型的双发射表面分子印迹纳米传感器，用于磺胺嘧啶的特异性吸附和检测。在该体系中，用二氧化硅包裹的蓝色发射碳量子点作为内标信号，以消除背景干扰，而红色发射巯基乙酸修饰的 CdTe 量子点（CdTe QDs）则作为识别信号被包裹在印迹层中。CdTe 量子点的荧光被猝灭，而碳量子点的荧光猝灭程度随磺胺嘧啶浓度的增加而不明显，从而反映出颜色的变化。磺胺嘧啶的检测在 0.25-20 μmol/L 的浓度范围内成功实现，检测限为 0.042 μmol/L，纳米传感器对磺胺嘧啶及其类似物具有特异性识别。与单发射荧光传感器相比，比率荧光纳米传感器具有更宽的线性范围和更高的检测精度。此外，该纳米传感器还成功地应用于实际水样和牛奶样品中磺胺嘧啶的测定，回收率可接受。该研究为磺胺嘧啶的检测提供了一种可行的方法，也为磺胺类药物的检测提供了参考。
