Tissue engineering (TE) is the process of creating tissue by combining appropriate cell and material combinations on particular scaffolds. Most normal tissue-derived cells, on the other hand, are anchorage-dependent and stay in extracellular matrices (ECMs).
The best 3D scaffold for a specifically engineered tissue should preferably be the correlating ECM in its native state. Nonetheless, native ECMs are operationally diverse, have complex compositions, and are highly dynamic, making it almost impossible to mimic such frameworks in vitro. As a result, a proper investigation into scaffold fabrication is required to improve TE development.
Customized scaffolds with controlled structure and scale are now a reality, thanks to rapid advancements in 3D printing technology. Furthermore, advanced optical 3D printing techniques have empowered the printing of cells, growth regulators, and numerous biocompatible materials onto complex 3D scaffolds that share functional and structural resemblances with native ECMs.
A team of researchers led by Professor Shih-Chi Chen from the Department of Mechanical and Automation Engineering, the Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China, has conducted a broad and up-to-date analysis of published optical 3D printing techniques for scaffold fabrication, such as material extrusion and jetting-based processes, selective laser sintering (SLS), stereolithography, and others.
The study was published in Light: Advanced Manufacturing.
The team examines the optical design, materials and representative applications, facilitated by a comparison of fabrication effectiveness. Fabrication accuracy, percentage, components and application scenarios are all crucial parameters to consider. Summaries and comparisons of each methodology are intended to enable readers in the optics and TE communities to choose the best printing approach for various application scenarios.
The researchers stated, “optical 3D printing methods are extremely effective due to their superior performance, cost-effectiveness, and the prospect of broader applications with emerging breakthroughs in new materials that address the fast-growing demand in 3D scaffold fabrication in TE.”
“In fact, we recognize a positive interplay among scaffold applications, materials, and 3D printing methods. In other words, the demand for advanced scaffold has been the driving force for the development in material and 3D printing methods and vice versa,” they added.
The researchers further clarified, “The fabrication of large-scale 3D scaffolds remains quite challenging, as optical 3D printing methods, especially TPP, achieves a much higher resolution (up to hundred nanometers) at the expense of printing time and ultimately the scaffold’s final size.”
“The FP-TPL technique recently developed by our team is capable of printing 3D structures with the highest throughput (10–100 mm3/h) and resolution (140/175 nm in the lateral/axial directions) ever reported and a 90% cost reduction (~US$ 1.5 /mm3) comparing with current commercial solutions, which may address the long-standing challenges in high-resolution large-scale scaffold fabrication,” they concluded.
Li, X., et al. (2022) Advanced optical methods and materials for fabricating 3D tissue scaffolds. Light: Advanced Manufacturing. doi.org/10.37188/lam.2022.026.