Department of Physics, School of Science, Hainan University, Haikou, 570228, China; School of Physical Science and Technology, Soochow University, Suzhou, 215006, China.
Department of Physics, School of Science, Hainan University, Haikou, 570228, China.
Biosens Bioelectron. 2022 Jan 15;196:113688. doi: 10.1016/j.bios.2021.113688. Epub 2021 Oct 6.
Detection of multiple analytes simultaneously in small liquid samples with high efficiency and precision is highly important to the fields like water quality monitoring. In this letter, we present a multiplexed nanosensors with position-encoded aptamer functionalized gold nanorods for heavy metal ions detection. The individual gold nanorods respond specifically to two different heavy metal ions (Pb and Hg) with a spectral shift in the scattering spectrum. We used a home-built spectral imaging dark-field microscope to measure the response of thousands of single plasmonic nanosensors with relatively high time resolution and precision. To explore the performance and limit of detection (LOD) of our nanosensor and setup, we recorded the concentration-dependent response of our position-encoded nanosensors with a series of mixture solutions that contain different concentrations of Hg and Pb ions. The LOD levels of our system are around 5 nM for Pb ions and 1 nM for Hg ions. Our method and results demostrate the nanomolar sensitivity and the potential to detect more different heavy metal ions.
在水质监测等领域，高效率、高精度地同时检测小液体样本中的多种分析物非常重要。在这封信件中，我们提出了一种基于位置编码的适配体功能化金纳米棒的多重纳米传感器，用于检测重金属离子。每个金纳米棒对两种不同的重金属离子（Pb 和 Hg）具有特异性响应，在散射光谱中出现光谱位移。我们使用自行搭建的光谱成像暗场显微镜，以相对较高的时间分辨率和精度测量了数千个单个等离子体纳米传感器的响应。为了探索我们的纳米传感器和设置的性能和检测限（LOD），我们用一系列含有不同浓度 Hg 和 Pb 离子的混合溶液记录了我们位置编码纳米传感器的浓度依赖性响应。我们系统的 LOD 水平约为 5 nM 的 Pb 离子和 1 nM 的 Hg 离子。我们的方法和结果表明，该系统具有纳摩尔级的灵敏度，并有可能检测更多不同的重金属离子。
