The main challenge in limiting the spread of the coronavirus (SARS-CoV-2) is the identification of infected people. Now, Japanese researchers have developed a new antibody-based method for rapid and reliable detection of COVID-19 that does not require a blood sample, writes Medical Xpress.
Currently, the predominant method of detecting the coronavirus is to collect nasal and throat samples by swabs. However, the application of this method is limited due to the long detection time (4-6 hours), high cost, specialized equipment, and the need for medical personnel.
An alternative and additional method of detecting COVID-19 is the finding of specific antibodies against the coronavirus. Test strips based on gold nanoparticles are now widely used in many countries for testing at places of medical care. They show sensitive and reliable results within 10-20 minutes. But they require finger-prick blood samples, and this is painful and increases the risk of infection or cross-infection.
In order to develop a minimally invasive method that would avoid these drawbacks, we have considered the idea of sampling and testing the interstitial fluid (ISF), which is located in the epidermis and dermis layers of human skin. Although antibody levels in ISF are approximately 15 to 25 percent of blood antibody levels, it was possible to detect anti-SARS-CoV-2 IgM/IgG antibodies and use ISF as a direct replacement for blood sampling, said researcher Leyli Bao from the Institute of Industrial Science, The University of Tokyo.