Researchers are using sound-waves and holograms to instantly mold tiny 3D shapes
Acoustic assembly could offer a strong alternative to bioprinting and rapid prototyping.
The idea of growing organs or tissues for medical use still sounds like science fiction — and indeed, it's an incredibly difficult thing to do. 3D-printing technology has shown some promise in the field of biofabrication, but the process is too slow, and often damages the tissue it's working with. Researchers in Germany may have a solution: using holograms and sound fields to rapidly assemble matter in 3D.
The process uses acoustic pressure to mold silica gel microspheres and other materials into complex 3D shapes. Pulling that off isn't easy. The team first had to learn how to create complex, layered holographic shapes that were formed from sound, rather than light — and that takes an incredible amount of computational power. "The digitization of an entire 3D object into ultrasound hologram fields is computationally very demanding and required us to come up with a new computation routine," one of the team's researchers told FastCompany.
Once the hologram is complete, however, it can be used to mold various materials. The shapes the team has made so far aren't very large — measuring less than an inch at the largest — but they are fairly complex. Even more impressive, the fabrication process happens quite quickly: One video included with the published study shows a clear cube with a cloudy liquid made of silica gel microspheres. Moments later, that cloud condenses into the shape of a helix.
Other experiments formed shapes using mouse myoblast cells, and the study's lead author, Kai Melde, told FastCompany that the technology had potential to be used for bioprinting in the future. "Ultrasound is gentle and non-toxic to the cells," Melde explained. "And the remote assembly without contact helps keep things sterile and the cells happy." The study also explores the idea of using the technology for targeted drug delivery and rapid prototyping. For now though, the research stands as an interesting proof of concept for rapid-one-step assembly of 3D objects, and a potential, much faster alternative to 3D printing in the future.