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Label-Free Single-Molecule Imaging with Numerical-Aperture-Shaped Interferometric Scattering Microscopy.

ABSTRACT: Our ability to optically interrogate nanoscopic objects is controlled by the difference between their extinction cross sections and the diffraction-limited area to which light can be confined in the far field. We show that a partially transmissive spatial mask placed near the back focal plane of a high numerical aperture microscope objective enhances the extinction contrast of a scatterer near an interface by approximately T-1/2, where T is the transmissivity of the mask. Numerical-aperture-based differentiation of background from scattered light represents a general approach to increasing extinction contrast and enables routine label-free imaging down to the single-molecule level.

SUBMITTER: Cole D

PROVIDER: S-EPMC5323080 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Label-Free Single-Molecule Imaging with Numerical-Aperture-Shaped Interferometric Scattering Microscopy.

Cole Daniel D Young Gavin G Weigel Alexander A Sebesta Aleksandar A Kukura Philipp P

ACS photonics 20170118 2

Our ability to optically interrogate nanoscopic objects is controlled by the difference between their extinction cross sections and the diffraction-limited area to which light can be confined in the far field. We show that a partially transmissive spatial mask placed near the back focal plane of a high numerical aperture microscope objective enhances the extinction contrast of a scatterer near an interface by approximately T-1/2, where T is the transmissivity of the mask ...[more]

PMID: 28255572

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