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Supercritical angle Raman microscopy: a surface-sensitive nanoscale technique without field enhancement.

ABSTRACT: Raman scattering microscopy is a versatile tool for label-free imaging and molecular fingerprint analysis. Here, we provide the first demonstration that the selective collection of scattered signals exceeding the critical angle for total internal reflection enables surface-confined spontaneous Raman investigations at nanometre resolution. This high-axial selectivity leads to improved signal-to-background ratios, thus making this technique an excellent probe for surface-related molecular specimens. The richness of the spectroscopic information obtained through the supercritical angle Raman (SAR) collection path was proven by comparing its output with that of a parallel far-field collection path. Furthermore, we demonstrated that the proposed SAR technique is a versatile microscopy approach that can be used alone or in combination with amplified Raman modalities such as surface-enhanced resonance Raman scattering.

SUBMITTER: Serrano D

PROVIDER: S-EPMC6061911 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Supercritical angle Raman microscopy: a surface-sensitive nanoscale technique without field enhancement.

Serrano Diana D Seeger Stefan S

Light, science & applications 20171020 10

Raman scattering microscopy is a versatile tool for label-free imaging and molecular fingerprint analysis. Here, we provide the first demonstration that the selective collection of scattered signals exceeding the critical angle for total internal reflection enables surface-confined spontaneous Raman investigations at nanometre resolution. This high-axial selectivity leads to improved signal-to-background ratios, thus making this technique an excellent probe for surface-related molecular specimen ...[more]

PMID: 30167204

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