Enhanced bioanalyte detection in waveguide confined Raman spectroscopy using wavelength modulation

Waveguide confined Raman spectroscopy (WCRS) incorporates a fibre based Raman detection system in a microfluidic platform enabling the spectroscopic detection of analyte. It offers the possibility to develop portable, alignment free devices for bio-analyte sensing with minimal sample preparation. Ultimate sensitivity is limited by the fibre auto-fluorescence background. Here we report enhanced bio-analyte detection sensitivity by combining WCRS with continuous wavelength modulation technique. We used urea as a model analyte and the modulation parameters have been optimized to maximize the sensitivity of the device.

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