The longer a gouge or scrape or similar laceration to the skin stays open, the greater the danger of infection. Closing a wound can require stitches, a procedure that carries problems and dangers of its own.

When skin is torn, white blood cells flood the damaged zone and release extracellular vesicles, which are tiny sacs of fat filled with fluids that fight inflammation, speed the formation of new blood vessels, and promote healing.

Still, healing of deep or otherwise severe wounds can take time.

Scientists at Nanjing and Suzhou universities in China decided to give nature a speed boost by filling in wounds with an extra dose of the vesicles.

The group has invented a pen—it looks a little like a dull pencil—filled with a material they call “portable bioactive ink for tissue healing,” or PAINT.

The pen combines extracellular vesicles and a gelling agent in its tip. The pen squirts the combination into a wound and the gel sets up within three minutes.

Once in place, the gelled vesicles kickstart the growth of epithelial cells, which form skin and other coverings inside and on the surface of the body, which also entrains the growth of blood vessels.

Mice with large wounds treated with PAINT were virtually completely healed at the end of 12 days, at least twice as quickly as mice left untreated.

TRENDPOST: Used in operating rooms or emergency rooms, PAINT could reduce the instance of post-treatment infections. With more than 300 million surgeries performed globally each year and 2 to 4 percent resulting in wound infections, the new technique could save hundreds of thousands of hours of extended hospital stays, countless needless medical treatments, and untold millions of dollars for insurance companies and the individuals paying their premiums.