The fabrication of perfusable hydrogels is crucial for recreating in vitro microphysiological environments. Existing strategies to fabricate complex microchannels in hydrogels involve sophisticated equipment/techniques. A cost‐effective, facile, versatile, and ultra‐fast methodology is reported to fabricate perfusable microchannels of complex shapes in photopolymerizable hydrogels without the need of specialized equipment or sophisticated protocols. The methodology utilizes one‐step ultraviolet (UV) light‐triggered cross‐linking and a photomask printed on inexpensive transparent films to photopattern PEG‐norbornene hydrogels. Complex and intricate patterns with high resolution, including perfusable microchannels, can be fabricated in <1 s. The perfusable hydrogel is integrated into a custom‐made microfluidic device that permits connection to external pump systems, allowing continuous fluid perfusion into the microchannels. Under dynamic culture, human endothelial cells form a functional and confluent endothelial monolayer that remains viable for at least 7 days and respond to inflammatory stimuli. Finally, approach to photopattern norbornene hyaluronic acid hydrogels is adapted, highlighting the versatility of the technique. This study presents an innovative strategy to simplify and reduce the cost of biofabrication techniques for developing functional in vitro models using perfusable three‐dimensional (3D) hydrogels. The approach offers a novel solution to overcome the complexities associated with existing methods, allowing engineering advanced in vitro microphysiological environments.
This content will become publicly available on August 1, 2024
While the human body has many different examples of perfusable structures with complex geometries, biofabrication methods to replicate this complexity are still lacking. Specifically, the fabrication of self‐supporting, branched networks with multiple channel diameters is particularly challenging. Herein, the Gelation of Uniform Interfacial Diffusant in Embedded 3D Printing (GUIDE‐3DP) approach for constructing perfusable networks of interconnected channels with precise control over branching geometries and vessel sizes is presented. To achieve user‐specified channel dimensions, this technique leverages the predictable diffusion of cross‐linking reaction‐initiators released from sacrificial inks printed within a hydrogel precursor. The versatility of GUIDE‐3DP to be adapted for use with diverse physicochemical cross‐linking mechanisms is demonstrated by designing seven printable material systems. Importantly, GUIDE‐3DP allows for the independent tunability of both the inner and outer diameters of the printed channels and the ability to fabricate seamless junctions at branch points. This 3D bioprinting platform is uniquely suited for fabricating lumenized structures with complex shapes characteristic of multiple hollow vessels throughout the body. As an exemplary application, the fabrication of vasculature‐like networks lined with endothelial cells is demonstrated. GUIDE‐3DP represents an important advance toward the fabrication of self‐supporting, physiologically relevant networks with intricate and perfusable geometries.more » « less
- NSF-PAR ID:
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Medium: X
- Sponsoring Org:
- National Science Foundation
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