3D printing deep in the body using ultrasound could deliver drugs, heal wounds

Ultrasound has been used to print polymers deep inside the body without damaging surrounding tissue. The protocol, which was demonstrated in animals, could have multiple applications such as drug delivery and wound healing.

3D printing has had a big impact on medicine, allowing the creation of patient-specific implants and tissue replacements. At present, however, these must be printed externally before being surgically implanted. It would therefore be highly desirable if doctors could inject biocompatible inks before curing them at the desired point. The opportunity for light-triggered polymerisation is limited, however, because even in tissue’s near-infrared ‘transparency window’, radiation is attenuated so quickly that printing more than a few millimetres beneath the skin is impossible.