An ultra-sensitive biosensor based on surface plasmon resonance and weak value amplification

Lizhong Zhang; Mingyi He; Yang Xu; Cuixia Guo; Chongqi Zhou; Tian Guan

doi:10.3389/fchem.2024.1382251

An ultra-sensitive biosensor based on surface plasmon resonance and weak value amplification

Front Chem. 2024 Mar 8:12:1382251. doi: 10.3389/fchem.2024.1382251. eCollection 2024.

Authors

Lizhong Zhang^#¹, Mingyi He^#², Yang Xu¹, Cuixia Guo³, Chongqi Zhou^{1

4}, Tian Guan¹

Affiliations

¹ Institute of Optical Imaging and Sensing, Shenzhen Key Laboratory for Minimal Invasive Medical Technologies, Shenzhen International Graduate School, Tsinghua University, Shenzhen, China.
² School of International Education, Beijing University of Chemical Technology, Beijing, China.
³ School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou, Fujian Province, China.
⁴ Department of Physics, Tsinghua University, Beijing, China.

^# Contributed equally.

Abstract

An ultra-sensitive phase plasmonic sensor combined with weak value amplification is proposed for the detection of IgG, as a model analyte. Phase detection is accomplished by self-interference between the p-polarization and the s-polarization of the light. With the principles of weak value amplification, a phase compensator is used to modulate the coupling strength and enhance the refractive index sensitivity of the system. On a simple Au-coated prism-coupled surface plasmon resonance (SPR) structure, the scheme, called WMSPR, achieves a refractive index sensitivity of 4.737 × 10⁴ nm/RIU, which is about three times higher than that of the conventional phase-based approach. The proposed WMSPR biosensor gives great characteristics with a high resolution of 6.333 × 10^-8 RIU and a low limit of detection (LOD) of 5.3 ng/mL. The results yield a great scope to promote the optimization of other SPR biosensors for high sensitivity.

Keywords: biomolecular interaction; biosensor; refractive index sensor; surface plasmon resonance; weak value amplification.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was financially supported by the Science, Technology and Innovation Commission of Shenzhen Municipality, China (Funding Number: KCXFZ20201221173207022) and the Development and Reform Commission of Shenzhen Municipality, China (Funding Number: XMHT20230115004).