Researchers at Oxford University have created a 3D printer capable of building with water. The printer extrudes tiny droplets of water into an oil-based solution. As the droplets come out, they get coated with the oil and retain their shape. The droplets also stick together, allowing the researchers to create tiny structures made entirely of water.

The researchers believe this printing method could help with tissue engineering. The 3D printed water networks aren't exactly human tissue, but they respond to electrical impulses in the same way.

"We aren't trying to make materials that faithfully resemble tissues but rather structures that can carry out the functions of tissues," said Professor Hagan Bayley of Oxford University's Department of Chemistry, who led the research. "We've shown that it is possible to create networks of tens of thousands of connected droplets. The droplets can be printed with protein pores to form pathways through the network that mimic nerves and are able to transmit electrical signals from one side of a network to the other."

The 3D printed water networks could be used to fill-in damaged areas of tissue, or even be used to help engineer transplantable body parts. Research to produce printed spinal inserts and kidneys is already in progress and both efforts require the printing of a scaffold that gets covered in cells. The Oxford researchers believe their newly developed network of water droplets could one day replace the scaffolds currently in use.

The Oxford water droplet research may also lead to advancements in drug delivery since the droplets could be programmed to carry medicine to specific areas of the body.

They produced an excellent video that details the process and explains why it may be important: