Tissue Engineering with combination of FDM and MEW:

Patient-specific treatments have become increasingly crucial in modern medicine. As personalized care gains prominence, the demand for innovative technologies to fulfill these requirements has arisen. Enter additive manufacturing (AM)—a promising solution that holds immense potential.

Researchers at the University of Otago aimed to combine two additive manufacturing techniques—fused deposition modeling (FDM) and melt electrowriting (MEW)—to create branched, hollow scaffolds for vascularization.

For this purpose, they initially created branched mold halves using computer-aided design (CAD) to support the MEW scaffold during construction. Subsequently, they proceeded to print using FDM conductive polylactic acid (cPLA) molds based on the CAD design. Afterward, MEW was performed over the FDM cPLA molds using FDA-approved polycaprolactone (PCL) biomaterial. Finally, the constructs were carefully removed from the molds post-print and heat-melded together to create hollow, branched structures.

The GeSiM BioScaffolder 3.1 was responsible for the MEW over the cPLA molds. Researchers placed the previously printed molds on a glass printing surface atop a high-voltage platform. The cartridge nozzle was positioned a few centimeters above the surface, ensuring precise alignment with the mold. The preprinting procedure involved activating pressure and voltage, touching the strand to the build plate, and then executing the print. This approach maintained a stable flow rate, preventing material blobs at the scaffold’s edges.

The scaffolds were then subjected to rigorous testing: dynamic mechanical analysis and in vitro cell growth. The scaffolds exhibited an anisotropic stiffness of either 1 MPa or 5 MPa, depending on the direction of applied stress. On the other hand, after a month of incubation, normal human dermal fibroblasts (NHDFs) were observed growing on the scaffolds. This demonstrated that the MEW scaffolds constructed using FDM cPLA molds had no deleterious effects.

On this study, a different printer was used for FDM. Current GeSiM BioScaffolders can be equipped with a GeSiM made FDM module for 1.75mm filaments. Therefore, this kind of hybrid print can now be done on one platform.

This hybrid additive manufacturing approach has potential for creating complex MEW scaffolds, particularly in tissue engineering applications related to vascularization, and we are excited to keep contributing to the development of such technologies with our machines.

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This article is based on the following publication:

[1] Thorsnes, Q.S.; Turner, P.R.; Ali, M.A.; Cabral, J.D. Integrating Fused Deposition Modeling and Melt Electrowriting for Engineering Branched Vasculature. Biomedicines 2023, 11, 3139. https://doi.org/10.3390/biomedicines11123139