A mcirofluidic device of biodegradable porous silicon nanowires for size based capturing and releasing viruses

A microfluidic device of porous silicon nanowire (PSNW) channel walls was fabricated as a point-of-care platform to capture nanoparticles (NPs) like viruses based on their sizes. PSNWs were synthesized on the bottom and sidewalls of the micro channels with metal-assisted etching. The space between PSNWs was controlled to capture NPs with a specific size. To enhance the capture rate, meandering channels were designed to increase the interaction between NPs and PSNWs by the Dean flow. With this system, we demonstrated label-free N5H2 avian influenza virus capture. In addition, virus can be released later and collected at the outlet by degrading PSNWs in PBS for 24 hours.