Trace detection based on concentrated reaction field in porous particle

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K14650
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 34020:Analytical chemistry-related
• Research Institution: University of Tsukuba
• Principal Investigator: Miyagawa Akihisa 筑波大学, 数理物質系, 助教 (80881599)
• Project Period (FY): 2021-04-01 – 2023-03-31
• Keywords: 微量計測 / 顕微分光 / マイクロ粒子 / DNA / 細孔性粒子 / タンパク質

Outline of Final Research Achievements

We have demonstrated that horseradish peroxidase (HRP) is concentrated several hundred-fold in silica particles, and single-stranded and duplex DNA are concentrated by approximately a thousand-fold. Using this concentration reaction field, we have shown the ability to quantify hydrogen peroxide at a concentration of 980 nM in a single-particle system. Additionally, we have elucidated the diffusion behavior of single-stranded and duplex DNA within the pores of silica particles. Single-stranded DNA tends to be distributed as aggregates within the particles, while duplex DNA readily dissociates inside the particles. By concentrating hairpin-type DNA within the particles and detecting target DNA based on the cleavage reaction of hairpin NDA, we have demonstrated the quantification of target DNA at a concentration of 10 nM in a single-particle system.

Free Research Field

分析化学

Academic Significance and Societal Importance of the Research Achievements

本研究では、シリカ粒子内に濃縮された分子を利用した計測原理を確立させた。その濃縮倍率などを定量的に議論している研究例はなく、学術的に意義深い。また、単一粒子系で顕微分光法によって計測を行うことにより、高感度な計測が可能となる。本計測法はレーザートラップやマイクロデバイスと親和性が高く、組み合わせることで簡便な検出システムを構築できるため、社会的貢献も見込める。また、DNAの粒子内の拡散挙動はクロマトグラフィーの分離機構を明らかにするための基礎知見となり、当該分野での学術的寄与を期待できる。