Development of a 3D3C super-resolution measurement method for flow velocity distribution in nanospace utilizing defocusing particle image with light interference

2022 Fiscal Year Final Research Report

• Project/Area Number: 19H02061
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 19010:Fluid engineering-related
• Research Institution: Keio University
• Principal Investigator: Kazoe Yutaka 慶應義塾大学, 理工学部(矢上), 准教授 (20600919)
• Co-Investigator(Kenkyū-buntansha): 花崎 逸雄 東京農工大学, 工学(系)研究科(研究院), 准教授 (10446734)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: ナノ流路 / 粒子画像流速計 / 超解像 / ナノ流体工学

Outline of Final Research Achievements

The field of fluid engineering has expanded to nanospaces smaller than the light wavelengths. When the space size becomes smaller than 1000 nm, various specific phenomena such as changes of liquid properties appear. Therefore, super-resolution measurements of flow velocity distribution with 10 nm spatial resolution become important for understanding of transport phenomena in nanospaces. In this study, by utilizing spherical aberration, which is a problem in the imaging, we developed defocusing nano-particle image velocimetry (PIV) to determine the position of nanoparticles with 10 nm spatial resolution based on particle images in the defocused region. Characteristics of defocused nanoparticle images with spherical aberration was revealed and a measurement system was constructed. We realized measurements of velocity distribution of nanoparticles migrating with pressure-driven flow in nanospace. This work will greatly contribute to advancements of various fields such as nanofluidics.

Free Research Field

マイクロ・ナノ流体工学

Academic Significance and Societal Importance of the Research Achievements

数10 nm～数100 nmのナノ空間における輸送現象は、ナノ流体工学といった先端研究分野だけではなく、細胞内・細胞間空間における機能の理解や、透析膜といった多孔質材料の開発など、様々な分野で重要なトピックである。本研究は、このようなナノ空間の中の現象を光の回折限界を超える10 nm分解能（超解像度）で捉えるための計測法を開発するものであり、生物物理、膜工学など様々な分野の発展に大きく寄与するものである。また、近年、超解像度計測法の開発が世界中で加速する中、本研究はこれらの計測法で実際の現象を捉えるための１つの設計指針を提案しており、超解像度計測法の発展に寄与できる点でも学術的意義が大きい。