3D printing of tissues and organs requires a bio-ink that can host the living cells that are required for every unique application. A viable construct requires an extracellular matrix that will have the right mechanical and biochemical properties for the intended cells. Researchers at Rutgers University believe they’re on track to being able to print a wide variety of tissues and organs thanks to a bio-ink that can be fine tuned so that living cells placed within structures printed using it will find comfort and proliferate as desired. The team used hyaluronic acid, a common biomolecule, and polyethylene glycol to create unique biocompatible gels. The bonds that form between the two molecules can be made to stiffen the gel to a specific strength, since some cells like stiffer surroundings while others like things to be soft. “Instead of an ink color for an inkjet printer, we want the mixture to have properties that are right for specific cells to multiply, differentiate and remodel the scaffold into the appropriate tissue,” said senior author of the study David I. Shreiber, in a Rutgers press release. “We focus on the stiffness of the gel and scaffold binding sites that cells can latch onto.” It is hoped that printers using the new bio-ink will accept cartridges of the two chemicals, as well as living cells and ligands that the cells bind to, to create tissues and organs that function like the originals they mimic, and even medical devices. “Both the stiffness and the binding sites provide important signals to cells,” said Madison D. Godesky, the lead author of the study. “What especially distinguishes our work from previous studies is the potential to control the stiffness and ligands independently through combinations of inks.” Source
