Advances in nanoprobes‐based immunoassays

Abstract Immunoassay is a powerful technique that uses highly specific antigen‐antibody interactions to detect biochemical targets such as proteins and toxins. As a diagnostic tool, immunoassay is employed in the screening, diagnosis, and prognosis of diseases, which are crucial for the grasp and control of patient conditions in clinical practice. With the rapid development of nanotechnology, immunoassays based on nanoprobes have attracted more and more attention due to the advantages of high sensitivity, specificity, stability, and versatility. These nanoprobes are nanoscale particles that can act as signal carriers or targeting agents for immunoassays. In this paper, we review the recent advances in various types of nanoprobes for immunoassays, such as colloidal gold, quantum dots, magnetic nanoparticles, nanozymes, aggregation‐induced emission, and up‐conversion nanoparticles. The effect of the nanoprobe construction and synthesis methods on their detection performance deserves to be studied in depth. We also compare their detection ranges and limits in different immunoassay methods, such as lateral flow immunoassays, fluorescent immunoassays, and surface‐enhanced Raman scattering immunoassays. Moreover, we discuss the benefits and challenges of nanoprobes in immunoassays and provide insights into their future development. This study aims to offer a comprehensive and critical perspective on the role of nanoprobes in the field of immunoassays.