Biomolecular Detection Based on Surface Enhanced Raman Scattering with Dielectrophoretic Manipulation

Plasmonic nanoarrays were used to localize surface plasmon for surface-enhanced acquisition of Raman signatures. To selectively capture and enhance Raman signals of the surface-enhanced Raman spectroscopy (SERS) system, we combine precise manipulation of target particles based on dielectrophoresis (DEP). Our system integrates metal nanostructures with interdigitated microelectrodes to enable the evaluation of the electrophysiological properties of microparticles. By modulating the frequency of the applied alternating current field, we can control particle movement based on their electrical characteristics, such as conductivity and permittivity. For the proof-of-concept, we have measured polystyrene (PS) beads as well as biological cells (U-87MG cell-line). Within this integrated system, SERS was performed with significantly increased efficiency. The real-time measurement of enhanced Raman scattering was achieved by dynamically controlling the force direction on individual particles, allowing us to selectively trap them on the nanostructured surfaces for analysis.