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bioRxiv · 10.64898/2026.02.04.703714

Reaction-enabled, highly sensitive super-resolution imaging

Zhu, W.·Gui, J.·Guo, A.·Zhang, Z.·Han, Z.·Zhao, W.·Feng, J.
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Abstract

Super-resolution microscopy breaking the optical diffraction limit has led to success in illuminating the complexity of biology with fluorescence--light-excited luminescence1,2. Here, we propose another approach for super-resolution imaging with electrochemiluminescence (ECL)--reaction-excited luminescence3,4. While featuring high sensitivity in molecular analytics owing to its laser-free excitation, the current reaction-driven imaging suffers from limited resolution due to low photon budget4. Efficient ECL imaging of intracellular organelles remains elusive. To meet this challenge, we develop RIED (Reaction-based super-resolution Imaging via Entropy-weighted correlation combined with Deconvolution), which builds upon two pivotal advancements: (i) unprecedented ECL intracellular organelles imaging through a 1,000-fold enhancement in ECL emission, and (ii) the super-resolution ECL imaging by the spatiotemporal acquisition and efficient utilization of highly dynamic ECL profiles. RIED allows for the first three-dimensional super-resolution ECL imaging with a spatial resolution of {bsim}97 nm in the lateral dimension and {bsim}235 nm in the axial dimension. This allows to reveal outer mitochondrial membrane topology and distinct microtubule organizations in different mitosis phases, offering a chemistry-based imaging capability for high-throughput imaging and highly sensitive interfacial imaging, which provides a new dimension into biology.

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Zhu, W., Gui, J., Guo, A., Zhang, Z., Han, Z., Zhao, W., Feng, J.. 2026-02-06. Reaction-enabled, highly sensitive super-resolution imaging. https://doi.org/10.64898/2026.02.04.703714

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