Recoverable elastic barrier for robust hydrogel patterning with uniform flow profile for organ-on-a-chip applications

Abstract

This paper presents a novel recoverable elastic barrier design that can realize robust hydrogel patterning without leakage or bursting from the central tissue chamber into the side microfluidic channels via the method of a temporary or virtual barrier. Compared with previous gel patterning methods using physical barriers like obstacle array or phaseguide microstructure, this method enables more uniform stimuli to the cultured cell/tissue and barrier-free imaging window. Besides the straight one-lane patterning, it also allows the irregular structural or multiple parallel cell-laden hydrogel compartments inside tissue chamber used for different applications. The effectiveness of this design is validated by its incorporation into a microfluidic platform for generating 3D vascularized organ-on-a-chip through different vascularization mechanisms of vasculogenesis and angiogenesis, respectively. We expect that this proof-of-concept will become a new and attractive method for gel patterning inside different microfluidic devices used for versatile biological applications such as organ-on-a-chip.