As space agencies around the world renew their lunar ambitions and private companies like SpaceX and Blue Origin set their sights on Mars, the medical challenges of long-term orbit are becoming increasingly critical. Beyond the technical hurdles of spacecraft engineering, the success of these missions depends on advanced medical care – specifically, the ability to treat severe injuries without Earth’s clinical infrastructure. To address this, BIH researchers have tested a 3D printer in microgravity that produces biological wound dressings for extensive burns and abrasions. Their findings have been published in Advanced Science.
Even the gold standard for treatment falls short
Treating severe burn wounds is a formidable task even on Earth, because they often go deep into the skin and cover a large surface area. As skin naturally heals from the edges inward, closing such wounds can be a protracted process, carrying a high risk of infection. To date, the gold standard for treatment is autologous skin grafting, which covers the wound to allow healing to begin from the center. Yet both the removal and transplantation of healthy skin come with complications, explains Professor Georg Duda, the study’s senior author and director of the Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration at the BIH. “Unfortunately, scarring is common,” he says, “and the medical and cosmetic outcomes are often unsatisfactory for both doctors and patients.” In their search for an alternative, Duda’s team partnered with the company Cellbricks, which provided the technical framework for the 3D printing process, while the researchers focused on developing the specialized “bioink.”
Skin patches straight from the 3D printer
“The ink consists of a mixture of living skin cells and a modified gelatin that hardens when exposed to UV light,” explains Bianca Lemke, the study’s lead author and a doctoral candidate under Professor Duda. Using a process known as digital light processing (DLP), the bioink solidifies layer by layer into a shape defined by UV light. This allows the form and size of the bandage to be tailored to the individual patient. “The consistency of the 3D printed dressing is similar to that of a gummy bear,” says Lemke. “The technology also allows for the printing of small tubular constructs, making the future integration of blood vessels possible.”
These bioprinted bandages can be produced on demand, with the entire printing process taking less than an hour regardless of the wound’s size. Because the bioink can incorporate a patient’s own skin or stem cells, the resulting treatment is fully personalized.
“Such an individual solution for burn wounds would also be practical for astronauts on the ISS or on the way to Mars,” says Georg Duda. “The idea was born at a symposium of the German Aerospace Center (DLR), where researchers began to wonder if 3D bioprinting could survive the rigors of space travel.” To find out, BIH researchers used parabolic flights to test whether the printing process remains effective under microgravity conditions. They specifically investigated whether the liquid ink could be printed as reliably as on Earth, if the gelatin would solidify precisely into the intended shape, and if the skin cells would be evenly distributed.
Printing results remain stable in microgravity
“Weightlessness would in principle provide perfect conditions because there are no gravitational forces to distort the printing process,” says Lemke. “But weightlessness on a parabolic flight only lasts 21 seconds per parabola. So we investigated how robust bioprinting is in the rapidly changing gravity environments of such experiments.” Parabolic flights produce short phases of microgravity (0G), normal Earth gravity (1G) and hypergravity (1.8G).
The findings showed that the bioprinting process was remarkably stable throughout the parabolic flights. The team achieved high marks for both accuracy and cell viability – the latter being a measure of how many skin cells survived the transition from the bioink to the wound patch. The only notable variation occurred during the hypergravity phases, where cells tended to settle on one side of the printed bandage. While Lemke acknowledges room for procedural improvement, she points out that this was caused by the flight's specific conditions. True weightlessness should ensure a more uniform distribution of cells within the bioink. The researchers are convinced that if the printing process works under such extreme conditions, it will also perform well in the sustained microgravity environment of space.
“These printing results bring us one step closer to actually providing astronauts with personalized wound care, while simultaneously offering a breakthrough in burn treatment for patients back on Earth,” says Georg Duda, “even if there’s still a long way to go.”
