Building muscle doesn’t always require eating more protein and pumping iron at the gym.
Chemists have been experimenting with various electrically conducting materials in hopes of creating “soft” artificial muscles that could power lighter, more flexible robots. Mike Marsella, a UCR assistant professor of chemistry, and graduate student Rodney Reid are trying to scale down the contracting and expanding characteristics of muscle to a single molecule, an advance that would lead to an array of applications in molecular electronics and nanotechnology.
Marsella and Reid have designed and synthesized an electrically conducting polymer composed of carbon-ringed building blocks called cyclooctatetraene which, in theory, should expand and contract when electrically stimulated. The work was reported in the journal Macromolecules in September.
The chemists say their design should allow the material to behave something like the bellows of an accordion when it expands and contracts. A single cyclooctatetraene is shaped somewhat like a half-open book, but opens flat when electrons are added or removed. By grafting the cyclooctatetraene to a polymer known to conduct electricity, the researchers reason, the phenomenon should work in a single macromolecule.
The next step in the chemists’ research is to demonstrate that such a system will work.
If it does work, the molecular muscle could find a variety of applications, including tiny military flying devices that carry sensors to detect chemical or biological warfare agents, biomedical devices and molecule-sized “fans” to cool microelectronic devices.
The research is supported by the National Science Foundation, American Chemical Society, Research Corporation and DuPont.