An image of the origami millirobot that may transfer by spinning. This robotic waits to ship a high-concentration medicament till it reaches the goal, versus capsules that should be ingested or liquids that should be injected. Credit: Zhao Lab
The tiny robots might convey well being care nearer to extremely exact medication supply
You most likely already know that drugs aren’t typically designed to focus on particular ache areas when you’ve ever taken the identical spherical pill to attempt to treatment the whole lot from complications to abdomen cramps. While many diseases have been handled with over-the-counter drugs for a few years, biomedical researchers have solely recently began wanting into strategies to deal with extra complicated medical issues like most cancers or heart problems extra successfully utilizing focused drug supply.
The millirobot is a possible growth on this growing area of biomedicine. With their means to crawl, spin, and swim into tight places on their mission to discover internal workings or distribute drugs, these fingertip-sized robots are set to turn out to be the longer term lifesavers in medication.
Renee Zhao, a mechanical engineer who leads analysis on this area at Stanford University, is growing quite a few millirobot designs concurrently, together with a magnetic crawling robotic that was not too long ago seen worming its approach by way of a abdomen on the duvet of Science Advances. Her robots can self-select numerous locomotive states and navigate obstacles throughout the physique as a result of they’re powered by magnetic fields, which permit for steady movement and might be utilized instantaneously to provide torque. Zhao’s staff has found a option to propel a robotic throughout the physique at distances ten occasions its size in a single bounce just by altering the magnetic area’s path and power.
A key side of her analysis, the magnetic actuation additionally gives untethered management for non-invasive operation and separates the management unit from the machine to permit for miniaturization. Zhao stated their most up-to-date robotic, not too long ago featured within the journal Nature Communications, is “the most robust and multifunctional untethered robot we have ever developed.”
This new “spinning-enabled wireless amphibious origami millirobot” is as multifunctional as its name implies. It’s an elegantly conceived single unit that’s able to speedily travel over an organ’s slick, uneven surfaces and swim through body fluids, propelling itself wirelessly while transporting liquid medicines. Unlike pills swallowed or liquids injected, this robot withholds medicine until “it reaches the target, and then releases a high-concentration drug,” said Zhao, who is an assistant professor of mechanical engineering. “That is how our robot achieves targeted drug delivery.”
Reshaping drug delivery
What’s groundbreaking about this particular amphibious robot, according to Zhao, is that it goes beyond the designs of most origami-based robots, which only utilize origami’s foldability to control how a robot morphs and moves.
On top of looking at how folding could enable the robot to perform certain actions – imagine an accordion fold that squeezes out medicine – Zhao’s team also considered how the dimensions of each fold’s exact shape influenced the robot’s rigid motion when it was not folded. As a result, the robot’s unfolded form inherently lends itself to propulsion through the environment. Such broad-minded considerations allowed the researchers to get more use out of the materials without adding bulk – and in Zhao’s world, the more functionality achieved from a single structure within the robot’s design, the less invasive the medical procedure is.
Another unique aspect of the design of the robot is the combination of certain geometrical features. A longitudinal hole into the robot’s center and lateral slits angled up the sides reduced water resistance and helped the robot swim better. “This design induces a negative pressure in the robot for fast swimming and meanwhile provides suction for cargo pickup and transportation,” Zhao said. “We take full advantage of the geometric features of this small robot and explore that single structure for different applications and for different functions.”
Based on conversations with Stanford Department of Medicine experts, the Zhao Lab is considering how to improve upon current treatments and procedures by building new technologies. If this work goes Zhao’s way, her robots won’t just provide a handy way to effectively dispense medicine but could also be used to carry instruments or cameras into the body, changing how doctors examine patients. The team is also working on using ultrasound imaging to track where robots go, eliminating any need to cut open organs.
The smaller, simpler, the better
While we won’t see millirobots like Zhao’s in real health care settings until more is known about optimal design and imaging best practices, the lab’s first-of-its-kind swimmer highlighted in Nature Communications is among their robots that are furthest along. It’s currently in the trial stages that come before any live animal testing that proceeds human clinical trials.
In the meantime, Zhao’s team continues combining a variety of novel smart materials and structures into unique designs that ultimately form new biomedical devices. She also plans to continue scaling down her robots to further biomedical research at the microscale.
As an engineer, Zhao strives to develop the simplest structures with the most functionality. Her amphibious robot exemplifies that mission, as it inspired her team to more fully consider geometric features not yet commonly prioritized by other origami robot researchers. “We started looking at how all these work in parallel,” Zhao said. “This is a very unique point of this work, and it also has broad potential application in the biomedical field.”
The study was funded by the National Science Foundation and the American Heart Association.
Reference: “Spinning-enabled wireless amphibious origami millirobot” by Qiji Ze, Shuai Wu, Jize Dai, Sophie Leanza, Gentaro Ikeda, Phillip C. Yang, Gianluca Iaccarino and Ruike Renee Zhao, 14 June 2022, Nature Communications.
DOI: 10.1038/s41467-022-30802-w
