Hierarchical biomaterials via photopatterning-enhanced direct ink writing

Abstract

Recent advances in additive manufacturing (AM) technologies provide tools to fabricate biological structures with complex three-dimensional (3D) organization. Deposition-based approaches have been exploited to manufacture multimaterial constructs. Stimulus-triggered approaches have been used to fabricate scaffolds with high resolution. Both features are useful to produce biomaterials that mimic the hierarchical organization of human tissues. Recently, multitechnology biofabrication approaches have been introduced that integrate benefits from different AM techniques to enable more complex materials design. However, few methods allow for tunable properties at both micro-and macro-scale in materials that are conducive for cell growth. To improve the organization of biofabricated constructs, we integrated direct ink writing (DIW) with digital light processing (DLP) to form multimaterial constructs with improved spatial control over final scaffold mechanics. Polymer-nanoparticle hydrogels were combined with methacryloyl gelatin (GelMA) to engineer dual inks that were compatible with both DIW and DLP. The shear-thinning and self-healing properties of the dual inks enabled extrusion-based 3D printing. The inclusion of GelMA provided a handle for spatiotemporal control of cross-linking with DLP. Exploiting this technique, complex multimaterial constructs were printed with defined mechanical reinforcement. In addition, the multitechnology approach was used to print live cells for biofabrication applications. Overall, the combination of DIW and DLP is a simple and efficient strategy to fabricate hierarchical biomaterials with user-defined control over material properties at both micro-and macro-scale.

Control of hydrostatic pressure and osmotic stress in 3D cell culture for mechanobiological studies

“…Integrating this basis with recent breakthroughs in tissue fabrication, biophysics, and biomaterials, should enable bottom-up strategies for the design of bioreactors that are well-suited to investigate the mechanobiology of HP and OS. Novel methods in 3D tissue bioprinting [159][160][161][162][163], mechanical characterization of biological tissues [164][165][166][167][168][169], the formulation of responsive biomaterials with tunable biomechanical and biochemical properties [170][171][172][173][174][175][176], and the development of 3D organotypic cell cultures [177][178][179][180][181][182] highlight a battery of innovations that can be exploited towards the design of advanced materials systems and bioreactors for the control of HP and OS.…”

Biopolymer Composites Material Extrusion and their Applications: A Review

“…DIW facilitates the Reproduced with permission. [140] Copyright 2020, IOP-Publishing. B) (a) Steps involved in printing porous carbon structure, (b) and (c) the printed designs before and after carbonization, and (d) a mechanical compression test on the porous cubic sample.…”

Structuring Hydrogel Cross-Link Density Using Hierarchical Filament 3D Printing

“…Additive manufacturing meets the challenge of organizing regions of finite cross-linking density, and dense, restrictive polymer networks (rather than voids). 10 Direct ink writing, 11 direct laser writing, 12 masked projection stereolithography, 2 and combinations thereof 13,14 have successfully been used to produce graded hydrogels that self-actuate as a result of the spatial patterning of their cross-linking density. However, these approaches are subject to the intrinsic limitations of additive manufacturing.…”