Functionalized paper SERS (P-SERS) substrates for selective targeting of analytes in complex samples

Surface enhanced Raman spectroscopy (SERS) requires the analyte molecule to be close to the plasmonic surface in order to generate SERS enhancement. This limitation restricts the practical application of SERS to molecules that possess functional groups that interact strongly with gold or silver surfaces. Moreover, the identification of target analytes in a complex sample matrix is made even more difficult when interferents compete with the target for binding to the plasmonic surface, resulting in overlapping spectral signatures. In this work, we report a strategy to functionalize inkjet printed P-SERS substrates by strategically placing supramolecular structures (such as nucleic acid aptamers) onto the gold nanoparticles. This promotes the selective interaction of target molecules with the plasmonic surface, leading to improved sensor performance.