"Biosensors for Pandemics 2021: Reliable and efficient nanotech-based diagnostics in emergency situations" is the 2nd edition of an Online conference that will address the main problems the scientific community is facing nowadays for COVID-19 pandemics. The idea is to get again together worldwide well-known experts in biosensing technologies who are working currently in COVID-19 diagnostics or have a great potential for the application of their technologies in the near future.