In this work we describe the development of an optofluidic device for surface enhanced Raman scattering (SERS) based detection of biological pathogens. The chip exploits the use of electro-active microwells which serve to both physically concentrate the Raman enhancers and to reduce the total analysis time through a unique electrokinetically driven on-chip mixing effect. To quantify the concentration performance of the device we use 44 nm polystyrene particles at low electric field strength (between 1.00–2.00 V) and demonstrate close to 90% concentration saturation within 2.5 s. We demonstrate the mixing capability through the enhanced detection of dengue virus serotype 2 (DENV-2). With DENV-2, we successfully detected the SERS signals with a limit of detection of 30 pM.
A dielectrophoretic chip with a roughened metal surface for on-chip surface-enhanced Raman scattering analysis of bacteria