As a bio/chemical sensing technique, surface enhanced Raman spectroscopy (SERS) offers sensitivity comparable to that
of fluorescence detection while providing highly specific information about the analyte. Although single molecule
identification with SERS was demonstrated nearly 20 years ago, today a need exists to develop practical solutions for
point‐of‐sample and point‐of‐care SERS systems. Recently, we demonstrated the fabrication of SERS substrates by inkjet
printing silver and gold nanostructures onto paper and other microporous membranes. Using these devices, we have been
able to achieve detection limits comparable to conventional nanofabricated plasmonic substrates. Furthermore, we leverage
the fluidic properties of paper to enhance the performance of the SERS devices while also enabling unprecedented ease of
Here we report the use of inkjet‐fabricated paper SERS substrates as a detection device for biological macromolecules in
an easy‐to‐use format with a low number of steps. The targeted biomarker is specifically detected with SERS through a
single step competitive displacement, which dramatically reduces the number of steps as compared to conventional assays.
Moreover, we further improve the usability of the assay by incorporating a paper SERS device with a fluidic cartridge
format. The wicking nature of the paper sensor eliminates manual sample application steps and is much simpler than the
world‐to‐chip interface of microfluidic devices. The introduction of this paper‐based SERS assay is a significant step
towards highly sensitive, low‐cost, and, importantly, easy to use multiplexed biological assays.