In keeping with Northeastern College, a breakthrough within the bioprinting of dwelling tissues might quickly result in 3D printing blood vessels and human organs. Guohao Dai, a bioengineering professor at Northeastern College, and his collaborators not too long ago patented a brand new elastic hydrogel materials designed for 3D printing of soppy dwelling tissues.
Fashionable medication makes use of 3D printing to create exhausting implants akin to cranial plates, hip joints, limb prostheses, and medical units. Nevertheless, the 3D printing of organs and gentle tissues continues to be a significant problem, says Dai, whose analysis focuses on 3D bioprinting, stem cells, and vascular bioengineering.
Smooth tissues require elastic supplies that may stretch and recoil – one thing present supplies lack. “Elasticity is essential for sustaining the traditional perform of the tissue,” mentioned Dai. Fixing this problem can revolutionize medication and make organ transplants out of date.
Hydrogels are artificial polymers able to holding water. They’re used, for instance, for facial masks that include pores and skin vitamins, wound dressings that ship medicine, and gentle contact lenses that include important quantities of water for consolation and oxygen transmission. In keeping with Dai, conventional hydrogels are too fragile for 3D printing, as they will’t face up to stretching or twisting – limiting their medical purposes.
To unravel this difficulty, Dai partnered with Yi Hong from the College of Texas Arlington. Whereas Hong discovered a strategy to make gentle hydrogels elastic, Dai used his experience in 3D printing to additional modify sure properties of those hydrogels so they might undergo a printer. To undergo the printing nozzle, the fabric needed to be liquid, however it additionally needed to hold its form after the item was printed.
The brand new materials dissolves in a liquid resolution and may encapsulate a considerable amount of water after printing. That is good for rising cells as a result of it mimics the surroundings of the human physique, which, on common, consists of 60% water.
Cells get infused into the liquid resolution earlier than printing. As soon as printed, the item is uncovered to blue gentle – triggering a photochemical response that makes the gel elastic with out harming the dwelling cells.
“You possibly can print any geometry,” mentioned Dai. ”You possibly can print a tube or a blood vessel.” The cells then multiply and develop contained in the printed construction. “We develop them underneath the pulsatile strain to imitate the human’s blood strain.”
One other key benefit of the brand new elastic hydrogel is that it’s biodegradable. The purpose was to make the polymer fully degradable – whereas cells substitute it with their very own collagen and elastin to type a robust, pure blood vessel. “It’s not native to your physique, that’s the reason we needed it to ultimately be gone fully,” mentioned Dai.
To date, the printed blood vessels – cultured for 2 weeks – stay comparatively weak and may’t but face up to human blood strain. Dai believes that extending the culturing interval to 2 months – which is an costly experiment – might enable the cells to completely develop a robust construction.
Moreover, the researchers are working to hurry up hydrogel’s degradation – aiming for it to dissolve inside two to a few months whereas the cells mature into practical blood vessels. This expertise is predicted to ultimately allow the creation of blood vessels for sufferers utilizing their very own cells. Because the hydrogel degrades, the physique will naturally substitute it – leading to totally practical tissue or organs.
