Xiong Jincheng, Sun Boyan, Wang Sihan, Zhang Shuai, Qin Linqian, Jiang Haiyang
National Key Laboratory of Veterinary Public Health Security, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, China Agricultural University, Beijing, 100193, China; Guangdong Provincial Key Laboratory of Advanced Biomaterials, Shenzhen Key Laboratory of Smart Healthcare Engineering, Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China.
National Key Laboratory of Veterinary Public Health Security, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China; Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, China Agricultural University, Beijing, 100193, China.
Talanta. 2024 Sep 1;277:126335. doi: 10.1016/j.talanta.2024.126335. Epub 2024 May 29.
Developing a simple, economical, sensitive, and selective method for label-free direct detection analytes is attractive, especially the strategies that could achieve signal amplification without complicated operations. Herein, a dual-fluorescence colorimetric nanoswitch sensing platform for label-free direct melamine (MEL) detection was established. We first explored the relationship between MEL-induced aggregation of gold nanoparticles (AuNPs) and size and determined the optimal size to be 37 nm. Using surfactant Triton X-100 to modify AuNPs and clarify possible interaction mechanisms to improve detection performance. The dynamic changes of surface plasmon resonance absorption peaks in the dispersed and aggregated states of AuNPs were skillfully utilized to match the emission of multicolor gold nanoclusters to trigger the multi-inner filter effect. Accompanied by the addition of MEL-induced AuNPs to change from dispersed to aggregated state, the fluorescence of green-emitting and red-emitting gradually turned on and turned off, respectively. The fluorescence turn-on mode detection limit was 10 times higher than the colorimetric method and as low as 5.5 ng/mL; the detection took only 10 min. The sensor detected MEL in spiked milk samples with a good recovery in the range of 81.2-111.0 % with a coefficient of variation less than 11.4 % and achieved a good correlation with commercial kits. The proposed sensor integrates numerous merits of label-free, multi-signal readout, self-calibration, simple operations, and economical, which provides a promising tool for convenient on-site detection of MEL.
开发一种简单、经济、灵敏且具有选择性的无标记直接检测分析物的方法很有吸引力，特别是那些无需复杂操作就能实现信号放大的策略。在此，建立了一种用于无标记直接检测三聚氰胺（MEL）的双荧光比色纳米开关传感平台。我们首先探究了MEL诱导的金纳米颗粒（AuNPs）聚集与尺寸之间的关系，并确定最佳尺寸为37 nm。使用表面活性剂吐温X-100修饰AuNPs并阐明可能的相互作用机制以提高检测性能。巧妙地利用AuNPs分散态和聚集态表面等离子体共振吸收峰的动态变化，使其与多色金纳米团簇的发射相匹配，从而触发多重内滤效应。随着MEL的加入导致AuNPs从分散态转变为聚集态，绿色发射和红色发射的荧光分别逐渐开启和关闭。荧光开启模式的检测限比比色法高10倍，低至5.5 ng/mL；检测仅需10分钟。该传感器在加标牛奶样品中检测MEL，回收率良好，在81.2 - 111.0%范围内，变异系数小于11.4%，且与商业试剂盒具有良好的相关性。所提出的传感器集成了无标记、多信号读出、自校准、操作简单和经济等诸多优点，为方便地现场检测MEL提供了一种有前景的工具。
