Imagine the day when a red warning message appears on surgical gloves after exposure to E.coli. Or envision a "smart" bandage that is loaded with antibiotics in a precise configuration, that can be used to treat your complex injuries. According to researchers at Tufts University and the University of Illinois at Urbana-Champaign, these breakthroughs could actually be delivered with little more than silk and an inkjet printer.
For some time now, scientists have tried to use common inkjet printers to print biomolecules, like enzymes, antibodies and growth factors. However, this effort has been limited by the heat-sensitive nature of these compounds. In other words, the higher temperatures generated in the printing process can cause biomolecules to lose their functionality.
This month, a new study published in the journal Advanced Materials, has identified purified silk protein, or fibroin, as an ideal candidate for inkjet printing. Not only does this natural polymer have strength, it also exhibits protective properties, that can “cocoon” or stabilize biomolecules.
By creating an inkjet-printable silk solution, the researchers were able to test a number of different applications, including a glove which notifies you if it’s contaminated. How does it work? Bacterial-sensing polydiacetylenes (PDAs), or agents that can detect specific bacteria, were printed onto surgical gloves. When the gloves were exposed to E.coli, the PDAs underwent a color change, causing the printed word “contaminated” to change from blue to red.
"We thought that if we were able to develop an inkjet-printable silk solution, we would have a universal building block to generate multiple functional printed formats that could lead to a wide variety of applications," said Fiorenzo Omenetto, Ph.D., senior author on the paper and Associate Dean for Research and Frank C. Doble Professor of Engineering at Tufts School of Engineering, in the press release.
By further developing these techniques, researchers might one day have surgical gloves that selectively react to different bacteria, thereby notifying doctors of any one of a number of infectious agents. And because antibiotics could be printed in a specific configuration, scientists may also be able to create "smart" bandages which are tailored to a particular injury.
Who would've thought? All of this from a little silk and an inkjet ink printer. "Indeed," said Omenetto in an email, "one of our goals is to extend the functionality of technology that we use everyday! The ability to simply add these kinds of functions to the printed format opens many possibilities."