According to Mark Skylar-Scott, one of the researchers, the hardest part was perfecting that technique. If the laser gets too close, it would harden the nanoparticles inside the nozzle and clog it. Plus, the structure could collapse if the system doesn't have perfect timing. Since they did manage to make it work, the method could be used to print out flexible and customized materials for wearables, sensors and medical devices in the future.

Wyss Institute Director Donald Ingber believes "This sophisticated use of laser technology to enhance 3-D printing capabilities not only inspires new kinds of products, it moves the frontier of solid free-form fabrication into an exciting new realm, demonstrating once again that previously accepted design limitations can be overcome by innovation." You can see the technique in action in the video below, but you can also read the team's study in detail on PNAS.