MEMS-assisted spatially homogeneous endothelialization of a high length-to-depth aspect ratio microvascular network.

The endothelialization of an engineered microvascular network is constrained by the mass transport of the endothelial cells through high length-to-depth (l/d) aspect ratio microchannels. This paper presents a deformable, reentrant microvascular scaffold as a microelectromechanical systems (MEMS)-assisted approach for spatially homogeneous endothelial cell seeding of high l/d (>200) aspect ratio microvasculature. Nickel electroplating and micromolding were employed for the fabrication of the polydimethylsiloxane (PDMS) reentrant microvascular scaffold. A 'stretch--seed--seal' ('3S') operation was implemented for uniform incorporation of endothelial cells on the luminal surface of the elastomeric constructs. Confocal microscopy was utilized to establish the uniformity of endothelialization and to demonstrate the feasibility of this strategy.