College of Chemistry, Nanchang University, Nanchang 330031, China.
College of Chemistry, Nanchang University, Nanchang 330031, China.
Food Chem. 2020 Jan 30;304:125377. doi: 10.1016/j.foodchem.2019.125377. Epub 2019 Aug 19.
We devise a novel colorimetric aptasensor for multiplex antibiotics based on an ss-DNA fragment coordinately controlling gold nanoparticles (AuNPs) aggregation. The multifunctional aptamer (Apt) was elaborately designed to be adsorbed on AuNPs surfaces acting as a binding element for antibiotics and a molecular switch. Chloramphenicol (CAP) and tetracycline (TET) were selected as the model antibiotics. When one kind of antibiotics was added, the specifically recognized fragment of Apt can bind to it and dissociated, and the non-specific one coordinately controls AuNPs aggregation under high-salt conditions. Hence, different color changes of AuNPs solution can be used as the signal readout. The aptasensor exhibited remarkable selectivity and sensitivity for separate detection of TET and CAP, and the detection limits are estimated to be 32.9 and 7.0 nM, respectively. The analysis with the absorption spectroscopy and the smartphone are applied to detect antibiotics in real samples with consistent results and desirable recoveries.
我们设计了一种新颖的基于 ss-DNA 片段协同控制金纳米粒子 (AuNPs) 聚集的多重抗生素比色适体传感器。多功能适体 (Apt) 被精心设计为吸附在 AuNPs 表面上，作为抗生素的结合元素和分子开关。氯霉素 (CAP) 和四环素 (TET) 被选为模型抗生素。当加入一种抗生素时，Apt 的特异性识别片段可以与之结合并解离，而非特异性片段在高盐条件下协同控制 AuNPs 聚集。因此，AuNPs 溶液的不同颜色变化可用作信号读出。该适体传感器对 TET 和 CAP 的单独检测表现出显著的选择性和灵敏度，检测限分别估计为 32.9 和 7.0 nM。通过吸收光谱和智能手机进行的分析应用于检测实际样品中的抗生素，结果一致，回收率理想。
