Electrochemiluminescence Microscopy: From Mechanism Deciphering to Biosensing

Electrochemiluminescence (ECL) is a luminous phenomenon in which the excited state luminophore is generated by dark electrochemical reactions in solutions. Due to its near-zero background, high sensitivity, good spatiotemporal controllability, fast detection and wide dynamic range, ECL has manifested itself to be one of the most successful techniques in in vitro diagnosis and clinical detection. In addition, ECL imaging possesses the unique advantages such as high-throughput and visualization. As a powerful surface analysis technology, ECL imaging has been successfully employed in material surface/interface analysis and bioanalysis. Given that the ECL intensity is highly dependent on the properties of electrode surface, ECL imaging can be used to investigate electron-transfer properties and the distribution of electrochemical activity of chemically-modified electrode. In the first part of this review, we briefly introduce the background of ECL technology and describe the generation mechanisms of ECL systems. Then we focus on the recent research progress of imaging analysis based on ECL microscopy, including mechanism rationalization, latent fingerprint visualization and single cell analysis. Finally, some perspectives and future directions of ECL are presented.