State Key Joint Laboratory of ESPC, School of Environment, Tsinghua University, Beijing 100084, China.
Cambridge Graphene Centre, Department of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom.
J Hazard Mater. 2023 Aug 5;455:131644. doi: 10.1016/j.jhazmat.2023.131644. Epub 2023 May 16.
Two-dimensional (2D) materials attract attention from the academic community due to their excellent properties, and their wide application in sensing is expected to revolutionize environmental monitoring, medical diagnostics, and food safety. In this work, we systematically evaluate the effects of 2D materials on the Au chip surface plasmon resonance (SPR) sensor. The results reveal that 2D materials cannot improve the sensitivity of intensity-modulated SPR sensors. However, there exists an optimal real part of RI of 3.5-4.0 and optimal thickness when choosing nanomaterials for sensitivity enhancement of SPR sensors in angular modulation. In addition, the smaller the imaginary part of the nanomaterial RI, the higher the sensitivity of the proposed Au SPR sensor. The 2D material's thickness needed for the highest sensitivity decreases with increasing real part and imaginary part of the RI. As a case study, we developed a 5 nm-thickness MoS-enhanced SPR biosensor, which exhibited a low sulfonamides (SAs) detection limit of 0.05 μg/L based on a group-targeting indirect competitive immunoassay, nearly 12-fold lower than that of the bare Au SPR system. The proposed criteria help to shed light on the 2D material-Au surface interaction, which has greatly promoted the development of novel SPR biosensing with outstanding sensitivity.
二维（2D）材料因其优异的性能引起了学术界的关注，它们在传感领域的广泛应用有望彻底改变环境监测、医疗诊断和食品安全。在这项工作中，我们系统地评估了 2D 材料对金芯片表面等离子体共振（SPR）传感器的影响。结果表明，2D 材料不能提高强度调制 SPR 传感器的灵敏度。然而，在选择纳米材料来增强 SPR 传感器的灵敏度时，对于角度调制，存在一个最佳的实部 RI 值为 3.5-4.0 和最佳厚度。此外，纳米材料 RI 的虚部越小，所提出的 Au SPR 传感器的灵敏度越高。对于最高灵敏度，所需的 2D 材料厚度随 RI 的实部和虚部的增加而减小。作为一个案例研究，我们开发了一种 5nm 厚的 MoS 增强 SPR 生物传感器，基于基团靶向间接竞争免疫分析，该传感器对磺胺类药物（SAs）的检测限低至 0.05μg/L，比裸金 SPR 系统低近 12 倍。所提出的标准有助于阐明 2D 材料与金表面的相互作用，这极大地促进了具有出色灵敏度的新型 SPR 生物传感的发展。
