Fig. 6.

Microfluidic devices for the culturing of cells in perfusable hydrogels. (A)In vitro development of vascularized tissue using perfusable collagen hydrogel. (a) Culturing device and cell system with medium perfusion. (b) The process of fabrication of vascularized 3D tissue based on a layer-by-layer technique. (c) Twelve-layer cell sheet on collagen hydrogel. (d) Six-layer cell sheet of cardiac muscle. Source: Sakaguchi et al. [134], copyright (2013), with permission from Nature Publishing Group. (B) Microvascular network in a collagen hydrogel, fabricated by micromolding. (a) The processes of fabrication and microvascularization. (b) Design of microfluidic device. (c) Confocal images of an established microvascular structure. Source: Zheng et al. [123], copyright (2012), with permission from the National Academy of Sciences.