On-chip chiral biosensor based on superchiral-field-enhanced Raman optical activity

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K14785
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 21060:Electron device and electronic equipment-related
• Research Institution: The University of Tokyo
• Principal Investigator: Xiao Tinghui 東京大学, 大学院理学系研究科(理学部), 客員共同研究員 (50869675)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: silicon photonics / optical sensor / Raman spectroscopy

Outline of Final Research Achievements

Raman optical activity (ROA) is effective for studying the conformational structure and behavior of chiral molecules in aqueous solutions and is advantageous over X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy in sample preparation and cost performance. However, ROA signals are inherently minuscule; 3-5 orders of magnitude weaker than spontaneous Raman scattering due to the weak chiral light-matter interaction. In this project, we demonstrated on-chip chiral biosensor by devising a silicon nanodisk array and exploiting its dark mode to overcome these limitations. Specifically, we use it with pairs of chemical and biological enantiomers to show >100x enhanced chiral light-molecule interaction with negligible artifacts for ROA measurements.

Free Research Field

Optics

Academic Significance and Societal Importance of the Research Achievements

このプロジェクトにより、X 線結晶構造解析法やNMR 分光法では不可能な、微量のキラル分子の絶対構造解析を、簡便・迅速・安価・安定的に行うことができる。分析化学、構造生物学、物質科学、薬学、量子生命科学などの多様な分野への応用展開が期待される。