Cilia have been difficult to replicate in engineering jobs, and are thought to be a technological phenomenon, particularly at the microscale. Essentially, the technique could one day allow for low-cost, portable diagnostic gadgets for manipulating cells, evaluating blood samples, and assisting in microfabrication processes.
Researchers have created a micro-sized artificial cilial system made of platinum-based components that can control fluid movement on such a small scale. The technology may one day allow for low-cost, portable diagnostic gadgets for analyzing blood samples, manipulating cells, or assisting in microfabrication processes.
Cornell University researchers recently developed micro-sized artificial cilia made of platinum-based components that can govern fluid movement on such a small scale. According to a Nanowerk article, cilia are the hardworking ushers of the body. These microscopic hairs, which move fluid via rhythmic beating, are responsible for pushing cerebrospinal fluid in an individual’s brain, eliminating phlegm and filth from the lungs, and keeping other organs and tissues clean.
Cilia are the body’s diligent ushers. These minute hairs are responsible for pumping CSF fluid in your brain, eliminating phlegm and dirt from your lungs, and keeping other organs and tissues clean. A technical marvel, cilia have proved difficult to reproduce in engineering applications, especially at the microscale.
It’s been very hard to use existing platforms to create cilia that are small, work in water, are electrically addressable and can be integrated with interesting electronics. This system solves these problems. And with this kind of platform, we’re hoping to develop the next wave of microfluid manipulation devices.
Wei Wang
Cornell researchers have created a micro-sized artificial cilial system made of platinum-based components that can control fluid movement at such a small scale. The technology may one day allow for low-cost, portable diagnostic gadgets for analyzing blood samples, manipulating cells, or assisting in microfabrication processes.
The research, “Cilia Metasurfaces for Electronically Programmable Microfluidic Manipulation,” was published in Nature, Wei Wang, a PhD student, is the principal author.
“There are numerous approaches of creating artificial cilia that respond to light, magnetic, or electrostatic stimuli,” Wang explained. “However, we are the first to employ our novel nano actuator to create individually controlled artificial cilia.”
The effort, led by the paper’s senior author, Itai Cohen, professor of physics in the College of Arts and Sciences, builds on a platinum-based, electrically-powered actuator (the part of the device that moves) that his lab previously developed to enable minuscule robots to walk. The mechanics of those bending bot legs are identical, but the cilia system’s function and applications are distinct and highly versatile.
“What we’re illustrating here,” Cohen explained, is that once you can individually address these cilia, you can alter the flows in whatever way you want. You can make many independent trajectories, circular flow, transport, or flows that divide into two routes and then recombine. You can get flow lines in three dimensions. Anything is possible.”
“It’s been very hard to use existing platforms to create cilia that are small, work in water, are electrically addressable and can be integrated with interesting electronics,” Cohen said. “This system solves these problems. And with this kind of platform, we’re hoping to develop the next wave of microfluid manipulation devices.”
A typical device is made up of 16 square units with 8 cilia arrays per unit and 8 cilia per array, with each cilium being about 50 micrometers long, resulting in a “carpet” of around a thousand artificial cilia. As the voltage on each cilium oscillates, its surface oxidizes and decreases on a regular basis, causing the cilium to bend back and forth and pump fluid at tens of microns per second. Different arrays can be engaged separately, resulting in an infinite number of flow patterns that resemble the flexibility seen in their biological counterparts.
As an added benefit, the scientists developed a cilia device with a complementary metal-oxide-semiconductor (CMOS) clock circuit – effectively an electronic “brain” that allows the cilia to operate without being connected to a traditional computer system. This opens the door to the development of a slew of low-cost diagnostic tests that may be conducted in the field.
“You can envision people in the future taking this tiny centimeter-by-centimeter device, putting a drop of blood on it, and running all the assays,” Cohen said. “You wouldn’t need a complicated pump or any other equipment; simply place it in the sunshine and it will operate. It could cost anywhere from $1 to $10.”
