【公開日：2024.07.25】【最終更新日：2024.05.28】
課題データ / Project Data
課題番号 / Project Issue Number
23HK0068
利用課題名 / Title
Development of label-free nanoplasmonic biosensing platforms
利用した実施機関 / Support Institute
北海道大学 / Hokkaido Univ.
機関外・機関内の利用 / External or Internal Use
外部利用/External Use
技術領域 / Technology Area
【横断技術領域 / Cross-Technology Area】（主 / Main）加工・デバイスプロセス/Nanofabrication（副 / Sub）-
【重要技術領域 / Important Technology Area】（主 / Main）量子・電子制御により革新的な機能を発現するマテリアル/Materials using quantum and electronic control to perform innovative functions（副 / Sub）次世代バイオマテリアル/Next-generation biomaterials
キーワード / Keywords
生体イメージング/ In vivo imaging,バイオセンサ/ Biosensor,電子線リソグラフィ/ EB lithography,フォトニクス/ Photonics
利用者と利用形態 / User and Support Type
利用者名（課題申請者）/ User Name (Project Applicant)
Lee Kuang-Li
所属名 / Affiliation
Biomedical Translation Research Center, Academia Sinica, Taiwan
共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes
Prof. Hiroaki Misawa,Prof. Yasutaka Matsuo,Prof. Xu Shi
ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes
Prof. Yasutaka Matsuo
利用形態 / Support Type
（主 / Main）機器利用/Equipment Utilization（副 / Sub）-
利用した主な設備 / Equipment Used in This Project
報告書データ / Report
概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)
Label-free sensing techniques, designed for the observation of dynamic cell activities, have the potential to advance studies in cell biology, immunotherapy, and drug discovery. In this context, we introduce the concept of Fano resonances featuring dual evanescent wavelengths in aluminum-coated nanoridge arrays for real-time and label-free analysis of cellular adhesion. The distinctive optical characteristics of dual evanescent lengths were confirmed through finite-difference time-domain (FDTD) calculations and experimental assessments, including tests of refractive index and surface (thickness) sensitivity. The findings reveal that the evanescent lengths measured 874 and 316 nm for the peak and dip of the Fano resonance at the air/aluminum interface, aligning with FDTD simulations (891 and 338 nm). Wavelength shifts and intensity variations of the Fano resonance correspond to changes in effective refractive index and absorption/scattering of surface plasmon waves, respectively. Employing four-parameter plots—time constants of Δλpeak, Δλdip, ΔImax, and ΔImin—we exemplify the investigation of long-range and short-range adhesion behaviors of lung cancer cells. In contrast to conventional gold-based SPR sensors with evanescent lengths ranging from 100 to 300 nm, the aluminum-coated nanoridge array exhibits an extended sensing depth and dual evanescent lengths. This dual capability enables the simultaneous exploration of cell behaviors in close proximity to and at a distance from the metal surface.
実験 / Experimental
Aluminum-coated nanoridges, characterized by a ridge width and height of 60 nm each, and a period of 470 nm, were produced on a polycarbonate (PC) substrate using hot embossing nanoimprint lithography and thermal evaporation. Initially, a 470-nm-period nanogroove array with a 5 × 5 mm2 area, a trench depth of 100 nm, and a slit width of 60 nm was generated on a Ni-Co mold through electron beam lithography (ELS-F125, Elionix, Japan) and electroplating. This metal stamp was then employed to replicate nanoridge arrays on a plastic film via hot-embossing nanoimprint lithography. Subsequent to depositing a 40-nm-thick aluminum film onto the plastic nanostructure, the aluminum-coated nanoridge arrays were formed.
結果と考察 / Results and Discussion
We introduced the concept of Fano resonances with dual evanescent lengths in aluminum-coated nanoridge arrays for real-time and label-free analysis of cellular adhesion. This method offers a dual sensing range and 4-parameter plots to characterize both long-range and short-range cell adhesion behaviors, including changes in cell morphology and mass redistribution within cells. The distinctive optical property of dual evanescent lengths was validated through FDTD calculations and experimental measurements, including refractive index and surface (thickness) sensitivity tests. Results revealed evanescent lengths of 874 and 316 nm for the Fano resonance peak and dip, respectively, at the air/aluminum interface, consistent with FDTD simulation findings (891 and 338 nm). The longer evanescent length of the Fano peak is sensitive to the cell-substrate adhesion interface, while the shorter length can penetrate deeper into the cellular medium. In comparison to conventional gold-based SPR sensors with evanescent lengths of 100-300 nm, the aluminum-coated nanoridge array exhibits an extended sensing range and dual evanescent lengths, enabling simultaneous investigation of cell behaviors near and far from the metal surface. This methodology presents a dual sensing range and 4-parameter plots, specifically time constants of Δλpeak, Δλdip, ΔImax, and ΔImin, facilitating the examination of long-range and short-range cell adhesion behaviors such as cell-cell and cell-substrate interactions. Importantly, the evanescent length can be tailored to any desired spectral range by adjusting the period of the nanostructures or the incident light angle. Additionally, when coupled with a hyperspectral imaging system, aluminum-coated nanoridge arrays can be employed for multiplex sensing of cell adhesion, contributing to high-throughput cell biological studies, immunotherapy, and drug discovery.
図・表・数式 / Figures, Tables and Equations
Manufacturing of aluminum-coated nanoridge arrays. (a) Schematic flowchart illustrating the fabrication process of metallic nanostructures using hot embossing nanoimprint lithography and a thermal evaporator. (b) Visual depiction of 96 aluminum-coated nanoridge arrays on a polycarbonate film, with each nanostructure covering an area of 5 × 5 mm2. (c) SEM image displaying the aluminum-coated nanoridges.
その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)
Technical support from “Advanced Research Infrastructure for Materials and Nanotechnology in Japan (ARIM)” of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) is acknowledged.
成果発表・成果利用 / Publication and Patents
論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)
-
Kuang-Li Lee, Aluminum-Coated Nanoridge Arrays with Dual Evanescent Wavelengths for Real-Time and Label-Free Cellular Analysis, The Journal of Physical Chemistry C, 128, 3384-3392(2024).
DOI: https://doi.org/10.1021/acs.jpcc.3c08016
口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.
特許 / Patents
特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件