Burns are nasty wounds, especially on a battlefield — lose a patch of skin more than 4cm in diameter, and it simply can't heal on its own. But skin grafts are often too cumbersome to apply in an urgent-care scenario. What if you could just stick a burned limb into a box that would print out a living skin graft directly onto the wound? Researchers at the Wake Forest Institute for Regenerative Medicine designed a prototype "bioprinter" that does just that. Here's a little documentary showing the device in action:
It acts just like your home printer, right down to the inkjet valve and vials of skin-cell "ink" that it sprays onto a wound. The printed skin graft consists of two separate layers — one is a mixture of skin cells with fibrinogen and Type I collagen (which each help with blood clotting and scar tissue formation, respectively); the second layer is thrombin, another clotting agent. The whole mixture has "a consistency similar to jello — so that [it] will adhere to the wound," say the researchers.
In order to print the insta-graft precisely onto the wound, a laser scans it beforehand to create a map that will be used to direct the computer-controlled printer head. Here's what one of those 3D maps looks like — if not for the Windows menu bar visible at the top of the screen, you'd think it came right out of Minority Report:
The researchers haven't tested it on humans in the field yet, but the results on mice were promising enough to warrant further study. Maybe we'll see these contraptions on neighborhood fire trucks in the year 2020.