Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh - 208016, India.
ACS Sens. 2020 Mar 27;5(3):645-649. doi: 10.1021/acssensors.9b02404. Epub 2020 Feb 24.
We present the concept of a nonlinear plasmonic sensing approach for rapid, sensitive, and label-free detection of mercury. Nonlinear plasmonic sensing of mercury relies on a systematic combination of nonlinear optics (NLO) with well-known concepts of amalgamation chemistry and plasmonic properties of gold nanorods. Exploiting the extreme sensitivity of the NLO process toward Hg-induced change in the local electric field of plasmonic nanorods, we succeed in improving the limit of detection (LOD) of mercury by 2-3 orders of magnitude as compared to the commonly used linear localized surface plasmon resonance (LSPR) based sensing. Using our method, an LOD of as low as 58 pM (11 ppt) has been achieved with high selectivity. Nonlinear plasmonic sensing aproach is found to work excellently for detecting mercury in real samples like blood plasma.
我们提出了一种非线性等离子体传感方法的概念，用于快速、灵敏、无标记检测汞。汞的非线性等离子体传感依赖于非线性光学（NLO）与众所周知的汞齐化学概念和金纳米棒的等离子体特性的系统组合。利用 NLO 过程对等离子体纳米棒局部电场因 Hg 引起的变化的极端灵敏度，我们成功地将汞的检测限（LOD）提高了 2-3 个数量级，与常用的基于线性局域表面等离子体共振（LSPR）的传感相比。使用我们的方法，已经实现了低至 58 pM（11 ppt）的检测限，具有很高的选择性。研究发现，非线性等离子体传感方法在检测实际样品如血浆中的汞时效果非常好。
