Microfluidic surface-enhanced raman scattering sensors based on nanopillar forests realized by an oxygen-plasma-stripping-of-photoresist technique

Abstract

A novel surface-enhanced Raman scattering (SERS) sensor is developed for real-time and highly repeatable detection of trace chemical and biological indicators. The sensor consists of a polydimethylsiloxane (PDMS) microchannel cap and a nanopillar forest-based open SERS-active substrate. The nanopillar forests are fabricated based on a new oxygen-plasma-stripping-of-photoresist technique. The enhancement factor (EF) of the SERS-active substrate reaches 6.06 × 106, and the EF of the SERS sensor is about 4 times lower due to the influence of the PDMS cap. However, the sensor shows much higher measurement repeatability than the open substrate, and it reduces the sample preparation time from several hours to a few minutes, which makes the device more reliable and facile for trace chemical and biological analysis. A novel microfluidic SERS sensor for real-time and highly repeatable detection is presented. The sensor employs noble metal-covered nanopillar forests as a SERS-active substrate. The nanopillar forests are produced by an oxygen-plasma-stripping-of-photoresist technique. The substrate is capped by a polydimethylsiloxane microchannel structure. Compared with open SERS-active substrates, the sensors have much higher measurement repeatability, and they reduce the sample preparation time from several hours to a few minutes. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.