A microfluidic surface enhanced Raman spectroscopic biosensor using aptamer functionalized nanopillars

This paper presents a microchip incorporating an aptamer-functionalized nanopillar substrate, enabling the specific detection of low-abundance biomolecules using surface enhanced Raman spectroscopy (SERS). In a temperature controlled microchamber, aptamers immobilized on the nanostructure surface specifically recognize target molecules. Raman-tagged biomolecules trapped within a cluster of leaning nanopillars report greatly enhanced Raman signals due to the coupling effect of localized surface plasmons. It was demonstrated that integrated intensities of spatially collected Raman responses are linearly proportional to analyte concentrations in the low picomolar regime (10/ 50/ 100/ 200 pM), showing the capability of our device for sensitive and quantitative detection of analyte molecules.