Recent Developments in Innovative Magnetic Nanoparticles-Based Immunoassays: From Improvement of Conventional Immunoassays to Diagnosis of COVID-19

During the ongoing COVID-19 pandemic, the development of point-of-care (POC) detection with high sensitivity and rapid detection time is urgently needed to prevent transmission of infectious diseases. Magnetic nanoparticles (MNPs) have been considered attractive materials for enhancing sensitivity and reducing the detection time of conventional immunoassays due to their unique properties including magnetic behavior, high surface area, excellent stability, and easy biocompatibility. In addition, detecting target analytes through color development is necessary for user-friendly POC detection. In this review, recent advances in different types of MNPs-based immunoassays such as improvement of the conventional enzyme-linked immunosorbent assay (ELISA), immunoassays based on the peroxidase-like activity of MNPs and based on the dually labeled MNPs, filtration method, and lateral-flow immunoassay are described and we analyze the advantages and strategies of each method. Furthermore, immunoassays incorporating MNPs for COVID-19 diagnosis through color development are also introduced, demonstrating that MNPs can become common tools for on-site diagnosis.

Automated summary

During the ongoing COVID-19 pandemic, there is an urgent need for point-of-care (POC) detection methods with high sensitivity and rapid detection time. Magnetic nanoparticles (MNPs) are attractive materials that can enhance the sensitivity and reduce the detection time of conventional immunoassays. This review discusses recent advances in different types of MNPs-based immunoassays and their advantages and strategies. Furthermore, the use of MNPs for COVID-19 diagnosis through color development is also introduced, demonstrating their potential as common tools for on-site diagnosis.