Waving a magic wand over an injured bone to create a custom, living repair patch sounds like something out of I, Robot. But researchers have created a handheld 3D-printing pen that could someday do just that. It's not magic, it's science.
The BioPen, developed at Australia's University of Wollongong, holds two different "inks:" one made of human cells, the other a protective, UV-activated structural gel. The pen layers the cells inside the protective gel, which hardens under the device's built-in UV light. Instead of the current weeks-long process of harvesting and growing replacement cartilage tissue, the compact, handheld device could enable doctors to "draw" functional material directly on to a damaged bone.
The benefit, as with most 3D-printed organs and body parts, is total customization. Instead of mass-produced orthopedic implants, which don't work exactly like human tissue, a matrix of human cells printed directly onto an injured bone would create actual, functional cartilage. And with the right mix of cells, growth factors, and drugs in the ink wells, doctors could even draw replacement tissue that would grow into functioning nerve or muscle tissue, with the protective scaffold biodegrading as the cells grew and matured.