Paper-based optofluidic SERS using ink-jet-printed substrates

Abstract

We report the development of a novel, low-cost surface enhanced Raman spectroscopy (SERS) substrate that is fabricated by ink-jet-printing silver nanostructures into cellulose paper. Analysis of a liquid sample is performed by spotting a 1 microliter droplet onto the printed SERS substrate. The droplet is contained within a small area of the SERS substrate by ink-jet-printing hydrophobic barriers to define microfluidic boundaries. Using Rhodamine 6G as the analyte, we are able to measure a strong SERS fingerprint signal when only 10 femtomoles of analyte are applied to the paper.