By: Jayden Neidell
Cilium, by definition, are short microscopic hairlike vibrating structures found in large numbers on the surface of certain cells, either causing currents in the surrounding fluid, or, in some protozoans and other small organisms, providing propulsion. Essentially, they help to move a cell or group of cells or help to transport fluid or materials past them. By programming these microstructures, creating artificial cilia, these devices could have greater flexibility and functionality than real cilia, which could reshape the delivery of healthcare and even improve the exploration of planets.
However, there has long been a significant barrier preventing these tiny devices from carrying out significant tasks: in addition to having to be minuscule, they also have to be able to bend and twist in order to perform the task at hand. Cellular species have cilia that can do such functions, but not on a large scale. Artificial cilia that can be more flexible than actual cilia may eventually provide a solution though, according to recent scientific developments.
Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have recently claimed that they have developed a single-material, single-stimuli microstructure that can outmaneuver even living cilia. To put it another way, unlike other advancements in the area, their invention just needs one substance to be designed and one trigger to move, in this example, light. This is because instead of relying on “complex multi-component materials,” they instead use only a photoresponsive liquid crystal elastomer. According to one of the researchers, their invention could alter “the methods we build materials and devices for a range of applications, including robotics, medicine, and information technologies.”
The researchers claim that the operation of this cilia is straightforward: When exposed to light, its components realign and the structure takes on a different shape. A perpetuation cycle begins as a result of those alterations. The microstructure will also undergo a new area of exposure to light, which will alter that region as well. This feedback loop creates a self-propelled and endlessly programmable microstructure. One of the Harvard researchers claims, “Once the light is turned on, it does all of its own work.” The “endlessly reconfigurable” twisting and turning of the artificial cilia is driven by their changing shapes, which the researchers anticipate is exactly what will make microstructures “potentially revolutionary” for a variety of applications requiring repetitive and specified movement.
Further, the possible applications of this material don’t end on Earth. NASA is now even studying how soft robots could explore the tight spots of a moon or planet using soft robotics driven by artificial cilia, showing even more how this discovery by Harvard researchers enables our society to achieve tasks that would otherwise be entirely out of reach.
