Research progress on electrochemiluminescence nanomaterials and their applications in biosensors - A review

Background: Electrochemiluminescence (ECL) is a promising analytical technique that combines electrochemistry with chemiluminescence. The performance of ECL systems depends on luminophores. Nonetheless, conventional luminophores present certain limitations. At first, their ECL efficiencies often fall short of the requirements for accurate detection. Moreover, in complex environments, traditional materials struggle to selectively identify target compounds and are prone to interference. Furthermore, these materials exhibit a deficiency in flexibility and tunability, attributed to their rigid structure and inherent characteristics. Advancing ECL technology necessitates the creation of novel materials that improve efficiency, selectivity, stability, and flexibility. Results: This review emphasizes the recent advances in ECL nanomaterials and their applications in biosensors. The discussion starts with a comprehensive examination of two main mechanisms of ECL emission: quenching ECL and co-reactant ECL. Various nanomaterials are then discussed, including semiconductor nanomaterials, metal nanoclusters, carbon nanomaterials, nanoscale aggregation-induced emission materials, organic nanomaterials, and composite nanomaterials, with emphasis on their unique ECL properties. Examples illustrate specific applications in disease diagnosis, environmental monitoring, and food safety testing. The review further examines the structural and luminescent characteristics of nanomaterials, which facilitate the advancement of novel ECL detection methodologies. Finally, we examine the existing challenges and propose possible avenues for the future advancement of innovative ECL nanomaterials. Significance: ECL nanomaterials possess unique quantum sizes and surface effects. Through the design and selection of appropriate nanomaterials, extremely sensitive, selective, and stable ECL biosensors may be developed for the detection of particular targets, applicable in disease diagnostics, food safety, and environmental monitoring.