Engineered nanoparticles for the management of COVID-19 and new variants of SARS-CoV-2

SARS-CoV-2 and its variants resulted in the global COVID-19 pandemic, creating a demand for innovative and effective strategies for prevention and diagnosis. This chapter provides a complete overview of the recent progress of engineered nanoparticles (NPs) used for the development of nano-vaccines (NVs) and point-of-care (PoC) sensors for combating COVID-19. It includes commercially available NVs and has an emphasis on the characterization, stability, preclinical testing, and human clinical trials. This chapter also details considerations related to safety, scalability, and regulatory aspects of NVs, aiming to provide a balanced understanding of the practical implications of employing nanotechnological solutions in the ongoing fight against COVID-19. The working principle related to the structural features of such engineered NPs, their surface modifications, and strategies for functionalization is also discussed. We discuss how engineered NPs could benefit PoC diagnostics, providing an overall view of their utility in managing SARS-CoV-2 and its variants. The use of various NPs and molecular recognition elements (MREs) for the development of sensors against SARS-CoV-2 using a multitude of techniques, including optical sensing with colorimetric assay and lateral flow tests (LFTs), in addition to electrochemical methods, is described in detail. The chapter provides a number of useful insights that can help drive future research and inform the development of adaptive strategies for mitigating COVID-19 and targeted interventions for dealing with SARS-CoV-2 variants during the postpandemic period.