Dendric nanostructures for SARS‐CoV‐2 proteins detection based on surface enhanced infrared absorption spectroscopy

Abstract

Infrared spectroscopy is a non‐destructive and rapid characterization tool that can distinguish different viral proteins by spectral details. However, traditional infrared spectroscopy has insufficient absorption signal intensity contrast when measuring low‐concentration samples. In this work, surface enhanced infrared absorption (SEIRA) spectroscopy is proposed by deploying a novel nanostructure array as SEIRA substrates. An array of gold dendric nanostructures are designed and fabricated with a precision resonance control to achieve surface enhancement covering a broadband molecular “finger‐print” region. The spectral positions of the multiple resonances accurately correspond to the characteristic absorption peaks of the SARS‐CoV‐2 proteins. An approach for SARS‐CoV‐2 protein detection based on SEIRA spectroscopy is then proposed. A low concentration detection of 40 μg/ml diluted SARS‐CoV‐2 nucleocapsid protein is experimentally demonstrated and the enhancement factor (EF) achieved is in good agreement with simulation results. The SEIRA methodology based on broadband resonance nanostructure design provides a systematic approach for sensitive, non‐destructive and rapid protein molecular detection, which could be extended to various kind of molecular characterization and biomedical diagnostics.

Label-free detection of MiRNA biomarkers using broadband multi-resonant infrared metasurfaces for early breast cancer diagnosis

“…Many nanostructures have been proposed, including zig-zag nanotips, nanorods, nanodiscs, nanoislands, etc. [13][14][15][16][17][18][19][20][21] Here, we demonstrate a multi-well SEIRA sensor chip based on metallic nanorod structures featuring a broad-band multiband resonance. The structures are specifically designed so that the resonances coincide with the absorption fingerprint regions of the target miRNA biomarkers, hence maximizing the light interaction with the biomarker molecules and collected SEIRA signals.…”

“…Many nanostructures have been proposed, including zig-zag nanotips, nanorods, nanodiscs, nanoislands, etc. 13–21…”