Microfluidic channels fabricated on mesoporous electrospun fiber mats: A facile route to microfluidic chips

We report a facile way of preparing microfluidic channels filled with electrospun functional fibers. Patterned elastic molds were in tight contact with electrospun fiber mats without any leak of the analyte solution. As an example of the simple devices, we demonstrated a microfluidic protein chip selectively purifying histidine‐tagged proteins. Highly mesoporous nitrilotriacetic acid‐functionalized polystyrene (PS‐NTA) fibers were produced by taking advantage of interpenetrating phase separation between PS and PEO during electrospinning. The specific interaction of Ni‐complexed PS‐NTA fibers with histidine enabled us to immobilize only target proteins from highly heterogeneous protein mixtures. The easy process to fabricate functionalized microchannels combined with the high production throughput from electrospinning may greatly contribute to chip‐based chromatographic and bioanalytical devices.