Direct imprinting of three-dimensional microfluidic scaffolds

Focusing on constructing complex internal microstructures in soft biomaterials, a novel method is presented to directly fabricate three-dimensional microfluidic scaffolds by combining layer-by-layer fabrication, microimprinting and freeze drying techniques. An automatic fabrication device is developed to realize the controllable processes containing solution casting, microstructure imprinting, freezing and layer binding, to make up poor repeatability and low efficiency in the traditional manual operations. The effects of mold treatment, surfactant addition in material solution as well as solution types on the microstructural replication are investigated. The results demonstrate that combining surfactant addition and guided casting process facilitate the precision fabrication of complex internal microfluidic channels in soft biomaterials.The presented scaffold fabrication process ensures the controllability and reproducibility of predefined microstructures.