The "active substance" is made from a hydrogel filled with bacteria programmed to glow when they react with certain chemicals. (Courtesy of researchers/MIT)
Luminous gloves made from "living materials" could one day replace the "gloves" currently used to detect certain substances in crime scene investigations and other scientific applications. CSI"-style black light, according to a new study
A team of researchers has bioengineered a "biomaterial" that reacts well when exposed to certain chemicals It will glow when. In the new study, researchers describe the biomaterial—a hydrogel filled with E. coli cells—and its potential applications. Fluorescence is used to genetically reprogram cells to glow when they are exposed to different chemicals.
So far, researchers have injected the hydrogel into gloves and bandages, but they say the active substance could be used in crime scene investigations, medical diagnostics, pollution monitoring and more. [Super-Smart Machines: 7 Robot Futures] "KDSPE" "KDSPs" "With this design, one could put different types of bacteria in these devices to indicate toxins in the environment, or diseases on the skin," study co-author, Timothy Lu, associate professor of bioengineering at MIT, said in a statement. We are demonstrating the potential of biomaterials and devices.
Although the target is wearable sensors, researchers have seen the most success testing programmed cells in petri dishes, where the environment can be carefully controlled. When living cells are deployed in a functioning device, maintaining them is a major challenge in the team's research.
To find a host for his programmed cells, Lu collaborated with Xuanhe Zhao, associate professor of civil, environmental and mechanical engineering at MIT. Zhao and his colleagues studied different hydrogel formulations, and their latest generation provides a stable environment for the bioengineered bacteria. The hydrogel, which is about 95 percent water, doesn't break when stretched or pulled, and it absorbs oxygen while fusing with a layer of rubber.
One test of the cell-filled hydrogel consisted of a bandage, or "living patch," programmed to respond to rhamnose, a natural sugar found in plants. The researchers also tested a glove whose fingertips glow when exposed to different chemicals. In both tests, the cells remained stable in the hydrogel and glowed appropriately in response to the chemicals.
For future biomaterials, the research team also developed a theoretical model to guide researchers in their designs.
"The model helps us design biological devices more efficiently," Zhao said. It tells you the thickness of the hydrogel layer that should be used, the distance between channels, how to design the channels, and how many bacteria to use.
The MIT team’s living materials were described in a study published online on February 15 in the Proceedings of the National Academy of Sciences.
Original article about life sciences.