UV Patterning of Cells in Microfluidic Devices for Tissue Engineering

Christiane Nguyen, University of Connecticut

Abstract: Bottom-up tissue engineering strategies are important to fabricate biomimetic tissue models for use in studying biological processes, understanding diseases, and screening new drug therapies. However, current fabrication techniques are limited in their ability to spatially distribute multiple cell types to mimic the complex architecture of human tissues. We have demonstrated the ability to fabricate and pattern 3D tissue constructs within 3D-printed microfluidic devices using a UV crosslinking approach. The cellular constructs are formed within 3D-printed microfluidic devices in order to expose the constructs to laminar fluid flow, providing oxygen and biomolecules and closely mimicking the in vivo microenvironment. In this way, cells can be cultured in a physiologically relevant microenvironment with 3D scaffolds and fluid flow, more accurately mimicking the conditions in vivo than 2D static cultures for biological experiments. Cells are encapsulated in photocrosslinkable hydrogels which are loaded into the device and crosslinked in desired patterns through customizable photomasks. Epifluorescence imaging was used to image cell viability and proliferation over the course of the experiment and cells have been shown to survive in the microfluidic culture environment under constant fluid flow over 7 days. The techniques and results presented here will improve accessibility of microfluidic fabrication for biological research, providing a convenient and physiologically relevant culture environment to carry out biological experiments in vitro.