Micropatterned macroporous structures in microfluidic devices for viral separation from whole blood.

Separation and enrichment of bio-nanoparticles from cell suspensions and blood are critical steps in many chemical and biomedical practices. We demonstrate here the design and fabrication of a microfluidic immunochromatographic device incorporating regular and multiscale monolithic structures to capture viruses from blood. The device contains micropatterned arrays of macroporous materials to perform size-exclusion and affinity chromatography in a simple flow-through process. The microscale gaps in the array allow the passage of cells while the macroporous matrices promote viral capture. Computational analyses reveal that fluid permeation into the porous matrices is controllable by the micropattern shape, separation distance and dimensions. Experimental analyses using blood samples containing human immunodeficiency viruses (HIV) as a model system further prove significantly improved viral capture efficiency using devices incorporating multiscale structures than those containing solid micropatterns. Such microfluidic devices with regular and multiscale structures have a potential for the separation and concentration of a wide range of bio-nanoparticles as well as macromolecules from complex mixtures containing both nano- and micro-sized species.