Breaking the diffusion-limit of the nano-plasmofluidic biosensing with two regimes of AC electrohydrodynamic flow

This paper reports the synergistic integration of plasmonics, microfluidics and electrokinetics to develop a label-free AC electrohydrodynamic-enhanced localized surface plasmon resonance (ACE-LSPR) biofunctional nanoparticle imaging technique to overcome performance barriers in diffusion-limited biosensing. In particular, we theoretically investigated the dynamic interplay between target molecule transportation and surface reaction, and simultaneously considered two AC electrohydrodynamic (AC-EHD) techniques: electroosmotic and electrothermal effects to achieve optimal mixing performance for biologically relevant fluids with different ion concentrations. Our preliminary experimental results have shown that the AC-EHD can significantly improve the limit of detection (LOD) by two-fold and shorten the assay time down to 20 minutes.