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arXiv · 1608.08002

Nanophotonic waveguide enhanced Raman spectroscopy of biological submonolayers

Ashim Dhakal·Pieter C. Wuytens·Frédéric Peyskens·Karolien Jans·Nicolas Le Thomas·Roel Baets
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Abstract

Characterizing a monolayer of biological molecules has been a major challenge. We demonstrate nanophotonic wave-guide enhanced Raman spectroscopy (NWERS) of monolayers in the near-infrared region, enabling real-time measurements of the hybridization of DNA strands and the density of sub-monolayers of biotin-streptavidin complex immobilized on top of a photonics chip. NWERS is based on enhanced evanescent excitation and collection of spontaneous Raman scattering near nanophotonic waveguides, which for a one centimeter silicon nitride waveguide delivers a signal that is more than four orders of magnitude higher in comparison to a confocal Raman microscope. The reduced acquisition time and specificity of the signal allows for a quantitative and real-time characterization of surface species, hitherto not possible using Raman spectroscopy. NWERS provides a direct analytic tool for monolayer research and also opens a route to compact microscope-less lab-on-a-chip devices with integrated sources, spectrometers and detectors fabricated using a mass-producible CMOS technology platform.

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Ashim Dhakal, Pieter C. Wuytens, Frédéric Peyskens, Karolien Jans, Nicolas Le Thomas, Roel Baets. 2016-08-29. Nanophotonic waveguide enhanced Raman spectroscopy of biological submonolayers. https://arxiv.org/abs/1608.08002

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