Planar SERS sensors and their potential in optofluidic systems

When molecules reside in close proximity to plasmonic nanostructures their Raman signals can be greatly enhanced, which enable the fast detection of molecules and the elucidation of structural information with high specificity and sensitivity. This effect is called surface-enhanced Raman scattering (SERS). In combination with microfluidic platforms, where reactions can be monitored in situ in flow-through experiments using very small sample volumes, this opens up new possibilities for biomedical and catalysis research. Prerequisite for such applications of SERS are stable and reproducible nanostructures. Here, we report on the construction of dedicated, planar SERS sensors based on the immobilization of different plasmonic nano¬particles on glass substrates via polymers and their application in reaction monitoring. To make use of the high amount of hyperspectral data that are generated during the experiments, automated pattern recognition tools and multivariate statistics are necessary. As an example results on the classification, identification and characterization of complex mixtures of biomolecules will be presented.