Specific and highly sensitive detection of volatile organic compounds by complex surface plasmon sensors with DNA aptamers

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K20996
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 21:Electrical and electronic engineering and related fields
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Shimizu Hiromasa 東京農工大学, 工学(系)研究科(研究院), 教授 (50345170)
• Project Period (FY): 2020-07-30 – 2023-03-31
• Keywords: SPRセンサ / 複素屈折率 / 揮発性有機化合物 / DNA / 強磁性金属

Outline of Final Research Achievements

We have tried the realization and improvement of the sensitivity of complex surface plasmon (SPR) sensor and selective detection of gas molecules by decoration of DNA in order to detect the volatile organic compounds in the gas phase with highly discriminative and sensitive characteristics. We have fabricated SPR sensor which composed of wedge-shaped Au thin film whose thickness is modulated inside the substrate, and evaluated the reflected light intensity every 10 seconds, by combination of a red light emitting diode, focusing lens, and camera. The obtained angle resolution was 0.0047 degrees, and we demonstrated the refractive index resolution of 0.000082. We have made a protocol that maximizes the signal based on the obtained series of the image, and successfully detected methyl salicylate of 7 ppb.

Free Research Field

光エレクトロニクス

Academic Significance and Societal Importance of the Research Achievements

水相中のたんぱく質とDNAの間に働く特異的相互作用を利用したバイオセンサについては数多くの報告例がある一方で、気体分子とDNAの間の相互作用に基づいたガスセンサについては、報告例が少ない。本研究では、DNAをSPRセンサに固定化し、気相中でガス分子を吸着する作用を見出し、ppm～ppbレベルのガスを検出できた、という点で学術的意義をもつ。また、ヒトが匂いを認識できる嗅覚閾値は1ppbから0.1ppbとされる。本研究では少なくとも7ppbのサリチル酸メチルを検出でき、嗅覚閾値まであと1桁というところまで到達し、嗅覚閾値を認識可能なセンサを視野に入れることができた、という点で社会的意義がある。