▲A biosensor that could specifically detect SARS-CoV-2, the virus which causes COVID-19.(sources: Freepik)
In response to the continuous spread of COVID-19, researchers around the world are working to improve the existing testing methods for virus screening. Teams at the Swiss Federal Laboratories for Materials Science and Technology (Empa) and ETH Zurich (Swiss Federal Institute of Technology in Zürich) co-developed a biosensor that could specifically detect SARS-CoV-2, the virus which causes COVID-19.
The Swiss research team was originally working on the development of biosensor that can measure, analyze and reduce airborne pollutants like aerosols and artificial nanoparticles. They have turned their investigations to develop a quick and reliable sensor to detect COVID-19 in the environment since the outbreak in Europe.
This detecting system uses an optical biosensor to screen the virus. They developed tiny "gold nanoislands" that contain artificially produced DNA receptor sequences, which are complimentary to sections of the SARS-CoV-2 virus’ RNA genome. These unique sequences are grafted onto the gold nanoislands and can reliably detect SARS-CoV-2. Hence, they are able to use "localized surface plasmon resonance (LSPR)" to detect whether an RNA sequence binds to the sensor.
To prevent false detection and inaccurate results, the research team combines thermal effects, "plasmonic photothermal (PPT)", which detects the virus through identifying different wavelength signals after heating the nanostructures, to increase reliability. However, they found that if the ambient temperature is much lower than the melting temperature, the biosensor may give false readings.
The biosensor is still in the early stage of development. The team cautioned that further development is necessary before it can be implemented and hopefully be applied to prevent future epidemics when fully developed.
Balfour, H. (2020) Developing a COVID-19 biosensor for faster diagnostics and environmental monitoring. European Pharmaceutical Review. 23 April. Available from: https://www.europeanpharmaceuticalreview.com/news/117659/developing-a-covid-19-biosensor-for-faster-diagnostics-and-environmental-monitoring/