Microscopically small cages can be produced at TU Wien (Vienna). Their grid openings are only a few micrometers in size, making them ideal for holding cells and allowing living tissue to grow in a very specific shape. This new field of research is called " Biofabrication ".
In a collaboration with Stanford University, nerve cells have now been introduced into spherical cage structures using acoustic bioprinting technology, so that multicellular nerve tissue can develop there. It is even possible to create nerve connections between the different cages. To control the nerve cells, sound waves were used as acoustic tweezers. Football shaped cages
If you present living cells with a certain framework, you can strongly influence their behavior," . "3D printing enables the high-precision production of scaffolding structures, which can then be colonized with cells to study how living tissue grows and how it reacts." Aleksandr Ovsianikov, Professor and Head, 3D-Printing and Biofabrication research group, Institute for Materials Science and Materials Technology, TU Wien
In order to grow large numbers of nerve cells in a small space, the research team decided to use so-called "buckyballs" - geometric shapes made of pentagons and hexagons that resemble a microscopic football.
"The openings of the buckyballs are large enough to allow cells to migrate into the cage, but when the cells coalesce, they can no longer leave the cage," explains Dr. Wolfgang Steiger, who worked on high-precision 3D printing for biofabrication applications as part of his dissertation.
The tiny buckyball cages were manufactured using a process known as two-photon polymerization: a focused laser beam is used to start a chemical process at specific points in a liquid, which causes the material to harden at precisely these points.
By steering the focal point of the laser beam through the liquid in a well-controlled way, three-dimensional objects can be produced with extremely high precision. Acoustic waves as tweezers