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bioRxiv · 10.64898/2025.12.05.692534

Quantitative STED microscopy with DNA-fluorophore labels

Kessler, L. F.·Li, Y.·Balakrishnan, A.·Heilemann, M.
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Abstract

Stimulated emission depletion (STED) microscopy enables super-resolution imaging of complex biological samples in 3D, in large volumes, and live. However, molecular quantification with STED has remained underexplored. Here, we present a straightforward approach for quantitative STED that enables molecule counting. For this purpose, we designed DNA-fluorophore labels that enable signal amplification and allow for reliable intensity-based quantitative imaging. We demonstrate accurate molecule counting on DNA origami. Furthermore, we visualized and quantified EGF receptor monomers and dimers in cells. In summary, we introduce a robust, fast, and easy-to-implement tool for quantitative STED microscopy with single-protein resolution.

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Kessler, L. F., Li, Y., Balakrishnan, A., Heilemann, M.. 2025-12-07. Quantitative STED microscopy with DNA-fluorophore labels. https://doi.org/10.64898/2025.12.05.692534

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