Right now, almost 70,000 people in the United States alone are on active waiting lists for organ donations. The dream of bio-printing is that one day, instead of waiting for a donor, a patient could receive, say, a kidney assembled on demand from living cells using 3-D printing techniques. But one problem with this dream is that bio-printing an organ outside the body necessarily requires surgery to implant it. This may mean large incisions, which in turn adds the risk of infection and increased recovery time for patients. Doctors would also have to postpone surgery until the necessary implant was bio-printed, vital time patients might not have.
A way around this problem could be provided by new bio-ink, composed of living cells suspended in a gel, that is safe for use inside people and could help enable 3-D printing in the body. Doctors could produce living parts inside patients through small incisions using minimally invasive surgical techniques. Such an option might prove safer and faster than major surgery.