Design and fabrication of magnetically functionalized flexible micropillar arrays for rapid and controllable
Bingpu Zhou1, Wei Xu, Ahad A Syed
1Nano Science and Technology Program and KAUST-HKUST Micro/Nanofluidic Joint Laboratory, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
Abstract:
Magnetically functionalized PDMS-based micropillar arrays have been successfully designed, fabricated and implanted for controllable microfluidic mixing. The arrangement of PDMS micropillar arrays inside the microchannel can be flexibly controlled by an external magnetic field. As a consequence, the flow fields inside the microchannel can be regulated at will via magnetic activation conveniently. When a microchannel is implanted with such micropillar arrays, two microstreams can be mixed easily and controllably upon the simple application of an on/off magnetic signal. Mixing efficiencies based on micropillar arrays with different densities were investigated and compared. It was found that micropillar arrays with higher density (i.e. smaller pillar pitch) would render better mixing performance. Our microfluidic system is capable of generating highly reproducible results within many cycles of mixing/non-mixing conversion. We believe that the simple mixing-triggering method together with rapid and controllable mixing control will be extraordinarily valuable for various biological or chemical applications in the future.
