Artificial muscles made of polymers can now be powered by glucose and oxygen, just like biological muscles. This new advance may be a decisive step towards grafts of artificial muscles into the human body or robots powered by biomolecules.
At Linköping University in Sweden, the study team presented their findings in the journal Advanced Materials.
The movement of our muscles is fueled by energy released when glucose and oxygen are involved in biochemical reactions. Likewise, artificial actuators made of polymers can convert energy into motion. Until yesterday it was only possible with electricity, even for the air robot.
Today, Swedish researchers have shown that it will be possible to move artificial muscles just as humans do. A conductive polymer, polypyrrole, which changes volume when crossed by an electric current, is the building block of new muscles.
How does it work?
The artificial muscle, known as the "polymer actuator" is made in layers. Three, to be precise, with two layers of polymer around a thin membrane in between. By positively charging one of the layers, the muscle contracts: with a negative charge it expands.
The electrons that cause this movement currently come from heavy batteries, which need to be charged continuously. The team of scientists in Sweden exploited the technology behind bioelectrodes, which convert chemical energy into electrical energy with the help of enzymes.
"These enzymes convert glucose and oxygen. It's just like our body does. You don't need batteries to produce the energy you need - just dip the muscle in the solution."
"When we integrated the enzymes on both sides of the actuator and saw it move it was fantastic," says Jose Martinez, a member of the research team.
Now what?
The next step will be to control the biochemical reactions in the enzymes, to make the movement of the muscles reversible and repeatable.
"Glucose is available in all organs of the body, it is the ideal substance.
Later we can also use other enzymes to ensure that autonomous microbots feed on the substances around them. An example? Small automatic droids to monitor the water of a lake, powered by the substances present in the same lake ".
A world of "natural" machines that exploit the dynamics of biology to move. Real biorobots.
