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A Colour-Encoded Nanometric Ruler for Axial Super-Resolution Microscopies

Optics 2023-11-02 v1 Quantitative Methods Subcellular Processes

Abstract

Recent progress has boosted the resolving power of optical microscopies to spatial dimensions well below the diffraction limit. Yet, axial super-resolution and axial single-molecule localisation typically require more complicated implementations than their lateral counterparts. In the present work, we propose a simple solution for axial metrology by providing a multi-layered single-excitation, dual-emission test slide, in which axial distance is colour-encoded. Our test slide combines on a standard microscope coverslip substrate two flat, thin, uniform and brightly emitting fluorophore layers, separated by a nanometric transparent spacer layer having a refractive index close to a biological cell. The ensemble is sealed in an index-matched protective polymer. As a proof-of-principle, we estimate the light confinement resulting from evanescent-wave excitation in total internal reflection fluorescence (TIRF) microscopy. Our test sample permits, even for the non-expert user, a facile axial metrology at the sub-100-nm scale, a critical requirement for axial super-resolution, as well as near-surface imaging, spectroscopy and sensing.

Keywords

Cite

@article{arxiv.2311.00590,
  title  = {A Colour-Encoded Nanometric Ruler for Axial Super-Resolution Microscopies},
  author = {Ilya Olevsko and Omer Shavit and Moshe Feldberg and Yossi Abulafia and Adi Salomon and Martin Oheim},
  journal= {arXiv preprint arXiv:2311.00590},
  year   = {2023}
}