Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs Lyngby, Denmark.
Biosensors (Basel). 2018 Sep 5;8(3):82. doi: 10.3390/bios8030082.
In this work, we developed a novel fluorescent sensor by combining molecularly imprinted polymers (MIPs) with graphene quantum dots (GQDs) for the determination of tetracycline (TC) in aqueous samples. Firstly, we developed a one-pot green method to synthesize GQDs as the fluorescent probes. GQDs with carboxyl groups or amino groups were fabricated. It was found that carboxyl groups played an important role in the fluorescence quenching. Based on these findings, the GQDs-MIPs microspheres were prepared using a sol-gel process. GQDs-MIPs showed strong fluorescent emission at 410 nm when excited at 360 nm, and the fluorescence was quenched in the presence of TC. Under optimum conditions, the fluorescence intensity of GQDs-MIPs decreased in response to the increase of TC concentration. The linear rage was from 1.0 to 10⁴ µg·L, and the limit of detection was determined to be 1 µg·L. The GQDs-MIPs also demonstrated high selectivity towards TC. The fluorescent sensor was successfully applied for the detection of TC in real spiked milk samples.
在这项工作中，我们开发了一种新型荧光传感器，通过将分子印迹聚合物（MIPs）与石墨烯量子点（GQDs）结合，用于测定水溶液中的四环素（TC）。首先，我们开发了一种一锅绿色方法来合成 GQDs 作为荧光探针。制备了具有羧基或氨基的 GQDs。结果发现，羧基在荧光猝灭中起着重要作用。基于这些发现，采用溶胶-凝胶法制备了 GQDs-MIPs 微球。GQDs-MIPs 在 360nm 激发下于 410nm 处显示出强荧光发射，而在存在 TC 的情况下荧光被猝灭。在最佳条件下，GQDs-MIPs 的荧光强度响应 TC 浓度的增加而降低。线性范围为 1.0 至 10⁴μg·L，检测限为 1μg·L。GQDs-MIPs 对 TC 也表现出高选择性。荧光传感器成功应用于实际加标牛奶样品中 TC 的检测。
