Electrochemiluminescence
(
ECL
) is a light‐emitting process triggered by electrochemical reactions. Thanks to its low background, high sensitivity, wide dynamic range, and rapid response time, ECL has manifested itself as a leading signal transduction technique in biosensing and bioimaging. In recent years, much effort has been expended to extend the readout of ECL signal from the conventional intensity measurement to spectral and imaging analysis.
ECL‐based spectroscopy
(
ECLS
) and
ECL‐based microscopy
(
ECLM
) are thus established and became two of the most popular electroanalytical methods. Recent advances in ECL analysis not only provide insightful information on ECL reaction mechanisms but also improve the analytical performance of ECL bioassays, particularly for multiplexing capacity and spatiotemporal resolution. In this monograph, we shall briefly introduce the fundamentals of ECL, and then focus on the progress of ECL bioassays that mainly include immunoassays, nucleic acid detection, enzymatic assays, and single‐cell analysis. Finally, some challenges and perspectives of ECL bioassays are discussed and presented. We believe that there are plenty of opportunities to design new ECL bioassays with high sensitivity, high throughput, and high spatiotemporal resolution.