A Hybrid Rapid Microfluidic Mixer Utilizing Electrokinetic Relay and Asymmetric Flow Geometries for Lab-on-a-Chip Applications

Numerical study on a rapid micromixer based on hybrid electrokinetic relay and asymmetric serpentine structures is presented. Effective mixing of liquids is essential in many applications such as drug delivery, DNA analysis/sequencing, pheromone synthesis in micro bioreactors, and biological/chemical agent detections. Rapid mixing can reduce the analysis time and permit high throughput in lab-on-a-chip or micro total analysis systems (μTAS). The proposed hybrid mixing takes advantages of both mixing enhancements induced by asymmetric flow geometries and the electrokinetic relay actuating. Simulation results show that the micro mixer is able to achieve high mixing efficiencies (94.3%) in short time (1.2s). Effects of relay frequency, electric field and channel geometry on micro-mixing have been conducted. Numerical results show that electrokinetic relay at an appropriate frequency causes effective micromixing. Moreover asymmetric flow geometries are critical for ultra effective mixing.