SERS detection of biomolecules with silver nanowires

Surface enhance Raman spectroscopy (SERS) has been demonstrated to be an efficient technique for identification of peptides, proteins, nucleic acids andother molecules of biomedical interest [1-3]. However, although substantial attempts have been made, the SERS detection of such species is still demanding and far from becoming a clinical tool. In particular, the development of plasmonic substrates specifically designed for sensitive, reproducible and rapid detection of biomolecules can offer the perspective of a reliable routine analysis. Here a strategy for label-free detection of proteins and biomarkers on a sub-micromolar concentration is presented. Silver nanowires are gathered on a filtration membrane under pressure producing a uniform coverage. Once tested on model proteins, the substrate exhibits high sensitivity as well as signal reproducibility throughout the whole silver surface. Then, the effective detection of Alzheimer's biomarkers is demonstrated. Strategies for optimizing the SERS response and reducing possible signal variability are presented. Overall, these substrates offer potential for development of cost-effective and flexible SERS assays of different targets of interest in the analytical and biomedical fields.