Guo Jiajia, Zhang Yan, Luo Yeli, Shen Fei, Sun Chunyan
Department of Food Quality and Safety, Jilin University, Changchun 130062, China.
Laboratory of Nutrition and Functional Food, Jilin University, Changchun 130062, China.
Talanta. 2014 Jul;125:385-92. doi: 10.1016/j.talanta.2014.03.033. Epub 2014 Mar 20.
We designed a turn-on fluorescence assay for glyphosate based on the fluorescence resonance energy transfer (FRET) between negatively charged CdTe quantum dots capped with thioglycolic acid (TGA-CdTe-QDs) and positively charged gold nanoparticles stabilized with cysteamine (CS-AuNPs). Oppositely charged TGA-CdTe-QDs and CS-AuNPs can form FRET donor-acceptor assemblies due to electrostatic interactions, which effectively quench the fluorescence intensity of TGA-CdTe-QDs. The presence of glyphosate could induce the aggregation of CS-AuNPs through electrostatic interactions, resulting in the fluorescence recovery of the quenched QDs. This FRET-based method has been successfully utilized to detect glyphosate in apples with satisfactory results. The detection limit for glyphosate was 9.8 ng/kg (3σ), with the linear range of 0.02-2.0 μg/kg. The attractive sensitivity was obtained due to the efficient FRET and the superior fluorescence properties of QDs. The proposed method is a promising approach for rapid screening of glyphosate in real samples.
我们基于巯基乙酸包覆的带负电荷的碲化镉量子点（TGA-CdTe-QDs）与半胱胺稳定的带正电荷的金纳米粒子（CS-AuNPs）之间的荧光共振能量转移（FRET），设计了一种用于草甘膦的开启式荧光检测方法。带相反电荷的TGA-CdTe-QDs和CS-AuNPs由于静电相互作用可形成FRET供体-受体组装体，这有效地淬灭了TGA-CdTe-QDs的荧光强度。草甘膦的存在可通过静电相互作用诱导CS-AuNPs聚集，导致淬灭量子点的荧光恢复。这种基于FRET的方法已成功用于检测苹果中的草甘膦，结果令人满意。草甘膦的检测限为9.8 ng/kg（3σ），线性范围为0.02 - 2.0 μg/kg。由于高效的FRET和量子点优异的荧光特性，获得了有吸引力的灵敏度。该方法是快速筛选实际样品中草甘膦的一种有前景的方法。
