Co-reaction accelerators for electrochemiluminescence: from fundamental mechanisms to advanced biosensing

Electrochemiluminescence (ECL) is a sensitive analytical technique, which converts electrochemical energy into electromagnetic radiation. With its high sensitivity, low background noise, and excellent controllability, ECL demonstrates significant application potential in fields such as bioanalysis, environmental monitoring, and food safety. However, traditional co-reactant-based ECL systems often suffer from low reaction efficiency and require relatively high concentrations of co-reactants to achieve satisfactory luminescence performance. The introduction of co-reaction accelerators (CRAs) offers an innovative strategy for constructing efficient and stable ECL systems by promoting the generation and transformation of reactive co-reactant intermediates. This review provides a comprehensive overview of the latest advances in CRAs. First, based on material composition, CRAs are categorized into three major categories: inorganic CRAs, bio-organic CRAs, and multifunctional CRAs. The fundamental principles of ECL and the underlying mechanisms of CRA-mediated signal enhancement are then discussed. We also summarize recent achievements of CRA-based ECL sensing platforms in detecting disease biomarkers and environmental pollutants, as well as in food safety applications. Finally, we discuss current challenges in this field and outline future development directions, aiming to provide valuable insights for the rational design of next-generation high-performance ECL analytical technologies.