a-SiC heteromorphic immersion nanocavities enabling wide-field real-time single-molecule detection

Qingxue Gao; Jinze Li; Wei Zhang; Zhiqi Zhang; Runhu Huang; Peilin Zang; Shuli Li; Chao Li; Jia Yao; Chuanyu Li; Zhen Guo; Lianqun Zhou

doi:10.1016/j.bios.2024.116962

a-SiC heteromorphic immersion nanocavities enabling wide-field real-time single-molecule detection

Biosens Bioelectron. 2024 Nov 19:270:116962. doi: 10.1016/j.bios.2024.116962. Online ahead of print.

Authors

Qingxue Gao¹, Jinze Li¹, Wei Zhang², Zhiqi Zhang², Runhu Huang³, Peilin Zang¹, Shuli Li³, Chao Li¹, Jia Yao¹, Chuanyu Li⁴, Zhen Guo⁵, Lianqun Zhou⁶

Affiliations

¹ School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, 230026, Hefei, China; CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, China.
² School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, 230026, Hefei, China; CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, China; Suzhou CASENS Co., Ltd, 215163, Suzhou, China.
³ CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, China.
⁴ School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, 230026, Hefei, China; CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, China. Electronic address: lichy@sibet.ac.cn.
⁵ School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, 230026, Hefei, China; CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, China. Electronic address: guozhen@sibet.ac.cn.
⁶ School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, 230026, Hefei, China; CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 215163, Suzhou, China. Electronic address: zhoulq@sibet.ac.cn.

PMID: 39579680
DOI: 10.1016/j.bios.2024.116962

Abstract

Real-time single-molecule detection via fluorescence exhibits advantages of non-contact and specificity, especially in illustrating the dynamic heterogeneity of living substances. However, wide-field view and signal-to-noise ratio (SNR) are always contradictory in real-time single-molecule detection with fluorescence labels, owing to the limitation of the omnidirectional radiation characteristics of fluorophores. Herein, we propose a nano optical sensing device based on a-SiC heteromorphic immersion nanocavities (aHINCs), enabling wide-field real-time single-molecule imaging without sacrificing SNR. The characteristics of architectural aHINCs for far-field imaging are investigated, and the designed sensing device help adjust the emission direction of fluorescence in gold hot spots of nanocavities, allowing the fluorescence divergence angle to be adjusted to ±10°. The experimental results show the SNR reached 22, markedly strengthening the fluorescence collection efficiency. The simultaneous observation of nanocavity sites, within the same field of view of the chip, is 488 times the number of sites observed with classic detection method. Furthermore, the wide-field real-time detection of the single molecule-specific binding process of the oligo DNA complementary chain is successfully realized. The nano optical sensing device based on the aHINC shows potential for parallel real-time single-molecule detection applications.

Keywords: Amorphous silicon carbide; Optical nanocavity; Parallel detection; Single-molecule fluorescence; Wide-field real-time detection.