Simulation and fabrication of capillary-driven meander micromixer for short-distance mixing

In recent years, the emerging bio-chip technology has used external powered pumps for fluidic pumping and mixing. The short-term capillary-driven micromixers with complex mixing structures also showed large potential for mixing devices. This reported work demonstrates the long-term capillary-driven meander micromixer with the planar design, short mixing distance and power-free rapid fluid, transport functions which is compared with conventional syringe pump micormixers. The surface property of various materials was verified by contact angle measurement. Both intrinsic hydrophilic materials of glass and JSR photoresist were good candidates and selected for fabricating the capillary-driven meander micromixer using simple photolithography, laser ablation and low-temperature bonding technology without chemical etching and without the deposition process. The design and simulation of such an effective capillary-driven micromixer have been performed for understanding the geometry effect on flow and mixing behaviour. The glass-JSR-glass capillary-driven meander micromixer can improve mixing efficiency up to over 95% at a short distance of only 8 mm, and has potential for the application of power-free microfluidic chip fabrication and bio-medical examination in the future.