A handheld surgical “pen” that works a little like a mini-3-D printer may soon be used to help repair damaged bones.

Surgeons could use the BioPen, developed by Australian researchers, to draw layers of stem cells directly at the site of an injury. After filling the damaged bone with the cells–mixed with a biodegradable seaweed extract to hold everything together–an ultraviolet light on the pen sets the gel in place.





Just as a 3-D printer deposits plastic one layer at a time, the BioPen deposits gel in layers to create a 3-D structure. “Biology works in 3-D,” says University of Wollongong professor Gordon Wallace, one of the researchers who is working on the project along with a team from the University of Melbourne. “The ability to provide an appropriate structural environment for the stem cells enables more effective development into the appropriate tissue.”

In the past, surgeons might have just injected stem cells instead. But by using the pen to build a small scaffold out of the gel, the cells can be better protected and more likely to survive. The researchers say it’s also easier to be precise with the pen in hand, and the whole process takes less time than surgeries would have in the past.

After the cells are in place, they multiply and eventually form functioning tissue. The device can also be used to apply growth factors to stimulate cell growth and other drugs. “It can be used in any instance wherein cartilage needs to be regenerated–it could be a sports injury or other traumatic event, or ‘wear and tear’ age-related degeneration,” Wallace says.





The prototype of the pen itself was built using a 3-D printer in the researchers’ lab. Wallace says next-generation fabrication techniques not only made it possible to easily build the pen, but they also make it possible to quickly iterate new versions of the hardware.

Now, partners at St. Vincent’s Hospital Melbourne are working on optimizing the cell material, and the researchers will start using the pen in animal trials later this year.