Bio‐Coreactant‐Enhanced Electrochemiluminescence Microscopy of Intracellular Structure and Transport

A bio-coreactant-enhanced electrochemiluminescence (ECL) microscopy realizes the ECL imaging of intracellular structure and dynamic transport. This microscopy uses Ru(bpy)₃²⁺ as the electrochemical molecular antenna connecting extracellular and intracellular environments, and uses intracellular biomolecules as the coreactants of ECL reactions via a "catalytic route". Accordingly, intracellular structures are identified without using multiple labels, and autophagy involving DNA oxidative damage is detected using nuclear ECL signals. A time-resolved image sequence discloses the universal edge effect of cellular electroporation due to the influence of the geometric properties of cell membranes on the induced transmembrane voltage. The dynamic transport of Ru(bpy)₃³⁺ in the different cellular compartments unveils the heterogeneous intracellular diffusivity correlating with the actin cytoskeleton. In addition to single-cell studies, the bio-coreactant-enhanced ECL microscopy is used to image a slice of a mouse liver and a colony of Shewanella oneidensis MR-1.