Bio-ink is a material made from living cells which behaves much like a liquid, allowing people to essentially print it in order to create a desired shape. This material was developed by researchers at the University of Missouri, Columbia, with the goal of someday being able to do things like print replacements for failing organs. As of 2008, bio-ink was only in the very early stages of testing and development, but it showed immense promise.

To make bio-ink, scientists create a slurry of cells which can be loaded into a cartridge and inserted into a specially designed printer, along with another cartridge which contains a gel known as bio-paper. After inputting the standards for the thing they want to print, the researchers trigger the printer, and the cartridges alternate layers to build a three dimensional structure, with the bio-paper creating a supportive matrix which the bio-ink can thrive on.

Through a process which is not yet totally understood, the individual droplets of bio-ink fuse together, eventually latticing upwards through the bio-paper to create a solid structure. Understanding this process and the point at which cells differentiate to accomplish different tasks is an important part of creating usable bio-ink; perhaps someday hospitals will be able to use bio-ink labs to generate tissue and organs for use by their patients.

The most obvious potential use for bio-ink is in skin grafting. Using bio-ink, labs could quickly create sheets of skin for burn victims and other people who might be in need of grafts. By using bio-ink derived from their own cells, patients could reduce the risk of rejection and unsightly scarring. Bio-ink could also be used to make replacements for vascular material removed during surgeries, allowing people to receive new veins and arteries.

Eventually, entire organs could be constructed from this material. Since organs are in short supply around the world, bio-ink could potentially save untold numbers of lives, as patients would no longer have to wait on the transplant list for new organs. The use of bio-ink organs could also allay fears about contaminated organ supplies, or unscrupulous organ acquisition methods.