‘Slow light’ detection of Covid-19 virus

‘Slow light’ detection of Covid-19 virus

Technology News |
By Nick Flaherty

Researchers in Korea have developed a novel biosensing platform to detect and quantify viral particles using a simple optical microscope and antibody proteins.

The research at the Gwangju Institute of Science and Technology is based on slowing down light using 100nm silico spheres and could pave the way to new diagnostic tools and next-generation detection platforms that are fast, accurate, and low-cost.

Related Covid-19 virus test articles

The research, led by Professor Young Min Song, uses the Gires–Tournois immunoassay platform (GTIP) based around a resonance structure. This is a film made from three stacked layers of specific materials that produce a peculiar optical phenomenon called ‘slow light.’

Because of how incident light rebounds inside the resonant layers before being reflected, the colour of the platform seen through an optical microscope appears very uniform. However, the nanometre-sized virus particles affect the resonance frequency of GTIP in their immediate vicinity by slowing down the light that gets reflected around them. This manifests as a vivid colour change in the reflected light so that, when viewed through the microscope, the virus particle clusters look like “islands” of a different colour compared to the background.

To ensure that their system only detects coronavirus particles, the researchers coated the top layer of GTIP with antibody proteins specific to SARS-CoV-2. This enabled the system to detect viral particles, but by using colorimetric analysis techniques could quantify the number of virus particles present in different areas of a sample depending on the colour of the light reflected locally.

The overall simplicity of the design is one of the main advantages of GTIP and is easily extended to machine learning vision systems for automated detection systems.

“Compared to existing Covid-19 diagnostic methods, our approach enables rapid detection and quantification of SARS-CoV-2 without needing extra sample treatments, such as amplification and labelling,” said Song.

GTIP is not limited to detecting viruses or strictly dependent on antibodies; any other binding agent works as well, helping visualize all kinds of particles that interact with light. “Our strategy can even be applied for a dynamic monitoring of target particles sprayed in the air or dispersed on surfaces. We believe that this approach could be the basis for next-generation biosensing platforms, enabling simple yet accurate detection,” he said.

Other articles on eeNews Europe

If you enjoyed this article, you will like the following ones: don't miss them by subscribing to :    eeNews on Google News


Linked Articles