Microfluidic immunoassays for point-of-care testing of SARS-CoV-2 antigens and antibodies

The point-of-care testing (POCT) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens and antibodies is of great significance in screening the infection and monitoring the in vivo immunity in controlling the pandemic. However, traditional immunoassays often require advanced laboratory settings with compromised potential in POCT. This article reviews recent advances in microfluidic immunoassays for POCT of SARS-CoV-2 antigens and antibodies. We first briefly introduce different diagnostic methods of coronavirus disease 2019 (COVID-19). After a concise introduction of different microfluidic platforms, we then focus on the latest advances in microfluidic immunoassays for POCT of SARS-CoV-2 antigens and antibodies based on different biosensing principles. In particular, some emerging biosensing principles such as photothermal biosensing are highlighted. At this end, we discuss the current challenges and future perspectives on this topic, which may shed light on new strategies on defense against similar coronavirus and other viruses to avoid pandemics in the future.