Bioprinting — 3D Printing Liquids That Stay Liquid
There have been many notable advances in the research into 3D Bio Printing in recent months and years for a number of specific applications. Leaving aside those focused on food, the production of human tissue using 3D printers is being researched at a number of leading institutions around the world for internal organs and external features. However, a new, breakthrough development involving the scaffolds needed to produce the living tissue from a research team at Oxford University in the UK brings with it some positive implications for the future of this discipline.
This current research is focused on the biodegradable scaffolds that are a prerequisite for all living tissue engineering as a base structure on which living cells are deposited and ‘grown’. Traditionally, research in this area has utilized scaffolds that are constructed from biologically-friendly, biodegradable solids or gels onto which the living cells are introduced. However, these solid and gel states do have limitations in terms of control and efficient growth of the cells — a liquid scaffold is one way that these limitations could be minimized and this is precisely what the team at Oxford has been working on.
The liquid scaffolds are created using a custom built 3D printer and demonstrate a sophisticated combination of physics and biology to achieve a 3D print that retains its liquid state. Essentially this custom 3D printer is using a deposition process but it is not printing out traditional ‘layers’ but rather single droplets. Each droplet (of water, for example) is coated with a lipid and is deposited through a special nozzle onto a platform submerged in oil where the droplets adhere to each other. The fact that water and oil repel each other is a key factor in the process outcome.
Gabriel Villar, former Oxford graduate student and the report’s lead author explains: “Instead of fusing to form a larger droplet, the tiny droplets ‘kiss’ and form a very thin bilayer interface because of their lipid coatings.”
So far, the research has seen the successful production of tens of thousands of droplets in this way. According to Villar there are multiple ways in which this research into printed liquid scaffolds will assist tissue engineering — and potentially drug delivery — in the future.
A video of the process can be viewed below: