石墨烯量子点荧光探针在磷酸盐检测中的应用

Fluorescent Graphene Quantum Dot Nanoprobes for the Sensitive and Selective Detection of Phosphate

本文以石墨烯量子点为荧光探针构筑了高选择性磷酸盐传感器.石墨烯量子点的荧光发射波长在407nm,Eu3+可使其荧光发生猝灭.随着磷酸盐的逐渐加入,Eu3+从石墨烯量子点的表面释放出来与磷酸盐结合,猝灭的荧光逐渐回升.回升的荧光信号与磷酸盐浓度成正比,线性范围为8.0×10-7到9.0×10-6mol/L,检出限为1.0×10-7mol/L.所制备的传感器具有较高的灵敏度和选择性,且测定简单,快速,使其具有一定的实际应用价值.

Graphene quantum dots （GQDs） were prepared by ultrasonic route and served as a highly selective water-soluble probe for sensing of phosphate. The fluorescence of GQDs with emission wavelength at 407nm was quenched by rare earth ion, europium （Eu^3 ＋ ） in proper concentration. With phosphate added gradually, Eu^3＋ ion progressively released from carboxylate modified GQDs and combined with phosphate. Concomitantly, the fluorescence intensity is recovered. The restored fluorescence is proportional to the concentration of phosphate. The linear range for the detection of phosphate was 8.0×10^-7 to 9.0×10^-6mol/L with a detection limit of 1. 0 ×10^-7mol/L. In addition, the constructed sensor with simple, sensitive and cost-effective properties makes it valuable for further application.