A team of scientists from the Institute of Physics of the Czech Academy of Sciences has reached a milestone in developing a method to detect the SARS-CoV-2 virus that causes the disease Covid-19. They have developed biochips that can detect the virus at the same speed as antigen tests and are as reliable as PCR. Recent research on the biosensors on which the system is based has confirmed their sensitivity and reliability, opening up new possibilities for further development.
“The advantage of biochips is that they can be reused repeatedly until a positive detection occurs. The best price-performance ratio for their use appears to be at the time when the pandemic will be fading and it will be necessary to prevent the disease from respreading, “said Hana Lísalová from the Institute of Physics of the CAS.
“The results of our current research were preceded by many years of work on the development of biochips designed to detect other pathogens, such as the causative agent of hepatitis or E. coli. After the outbreak of the Covid-19 pandemic, we had the idea of using them for the detection of SARS-CoV-2,” she stated.
The basic research has now been completed and the functionality and reliability of the biochips have been demonstrated. The results of the research have been published in the prestigious ACS journal Applied Materials and Interfaces. Lísalová is optimistic that the technology could be put into practice very soon.
The new variant should not reduce detection sensitivity
The breakthrough technology combines physical, chemical, and biological principles. The system works based on a functional biochip on which a thin layer of polymer is deposited. Antibodies are then bound to it to detect the virus. Thanks to this special treatment, other particles on the biochip are not trapped and are washed away.
The antibodies bound react to the viral N-protein, which is more stable and does not undergo mutations to the same extent as the S-protein. According to Lísalová, this is being proven with the appearance of new variants of the SARS-CoV-2 virus.
“Mutations avoid the N-protein because it is more stable, so even if a new variant emerges, it should not affect the sensitivity of detection. This can also be inferred from the fact that we have been using the biochip for a year and a half, so we have encountered multiple coronavirus variants. This is a big advantage for the future, “she commented.
Reliable and fast
The method also benefits from the absence of sample conditioning, where the detected N-protein forms complexes with the viral RNA, so the detection is naturally amplified. This makes the method not only similarly reliable but also significantly faster compared to PCR tests, which require the isolation of viral RNA first.
Virologists from the Biological Centre of the CAS and the Faculty of Science of the University of South Bohemia in České Budějovice also participated in the development and optimization of the biochip.
According to Lísalová, cooperation with other scientific institutions in the Czech Republic and abroad also proved crucial. “In particular, the cooperation with the team of An-Suei Yang from Academia Sinica in Taiwan, who developed and provided us with the antibodies, played a vital role in the development of our research, ” she added.