Printed life Simple 3D printer processes living tissue

Previously, the so-called bioprinting required expensive specialized equipment. However, researchers from Munich have now modified a simple 3D printer for this purpose...

Tissue engineering is a technology of the future, researchers believe. Artificially produced, functional tissue—such as cartilage, bone, or muscle tissue—potentially offers many applications. Consider pharmacology, where the benefits and side effects of medications need to be tested. And in medicine, it can be used to treat patients with tissue damage. However, producing complex tissue with the same properties as natural tissue has been quite challenging. Although progress has been made, we are still far from the goal of manufacturing tailored tissue on a larger scale. To further develop tissue engineering, experts around the world must cooperate, generate, and share knowledge, emphasize the bioengineers at the Center for Applied Tissue Engineering and Regenerative Medicine (Canter) at Munich University of Applied Sciences.

How to build an affordable bioprinter

Previously suitable printing systems also cost several tens of thousands of euros, as emphasized by the Munich researchers. However, there is a more cost-effective solution! In collaboration with an interdisciplinary team at Canter and the Technical University of Munich (TUM), researcher Benedikt Kaufmann modified a few hundred euros’ worth of a 3D printer from an electronics store, which is normally used for making plastic prototypes and models, to also print living tissue. The open-source construction manual is now also freely available to everyone. The greatest challenge was in creating the suitable environmental conditions. For processing proteins and cells, a high humidity level and a consistent 37 degrees Celsius are needed. However, heating foils attached to the aluminum housing of the printer and controlled by a microcontroller provide the necessary temperature. Water-soaked cellulose ensures an air humidity of over 90 percent. Additionally, the metallic printing platform, which would typically build up the plastic structures layer by layer, was replaced by a mounting on which a transparent glass slide can be attached. On this, biomaterials and cells can be directly printed and then examined under the microscope at high resolution.

A dwarf prints on par with the giants

Additionally, the printer uses masked stereolithography, a particularly cell-friendly process in which light from LEDs is projected through a liquid crystal display—similar to those of a smartphone or computer monitor—onto a glass slide coated with a gelatin-like hydrogel according to a pre-programmed pattern. Individual pixels of the display are selectively activated. This ensures that the proteins in the hydrogel precisely cross-link and solidify at the desired locations. Layer by layer, a three-dimensional structure is formed. While the modified 3D printer may appear almost dwarf-like compared to the professional devices in the Canter laboratory at Munich University of Applied Sciences, the results it delivers are emphasized to be on par with those of the larger machines.

“This article was first published on our sister portal "Industry of Things" (German Edition), Vogel Communications Group.“