Strength in numbers: Students dig in to (i)Help
The stamp is nearly 1 centimeter across and is built of layers of a hydrogel made of polyethylene glycol (an FDA-approved polymer used in laxatives and pharmaceuticals) and methacrylic alginate (an edible, Jell-O-like material).
The stamp is porous, allowing small molecules to leak through, and contains channels of various sizes to direct the flow of larger molecules, such as growth factors.
The researchers tested the stamp on the surface of a chicken embryo. After a week the stamp was removed, revealing a network of new blood vessels that mirrored the pattern of the channels in the stamp.
“This is a first demonstration that the blood vessels are controlled by the biomaterials,” Kong said.
The researchers see many potential applications for the new stamp, from directing the growth of blood vessels around a blocked artery, to increasing the vascularization of tissues with poor blood flow, to “normalizing” blood vessels that feed a tumor to improve the delivery of anti-cancer drugs. Enhancing the growth of new blood vessels in a coordinated pattern after surgery may also reduce recovery time and lessen the amount of scar tissue, the researchers said.
In another study published earlier this year, the team developed a biodegradable material that supports living cells. Future research will test whether the new material also can be used a stamp.
Researchers on the study team also included K. Jimmy Hsia, a professor of mechanical science and engineering and of bioengineering at Illinois; postdoctoral researchers Jae Hyun Jeong and Pinar Zorlutuna; and graduate students Vincent Chan, Chaenyung Cha and Casey Dyck.