By using bacterial flagella as a template for silica, researchers have demonstrated an easier way to make propulsion systems for nanoscale swimming robots.
A feature of science fiction stories for decades, nanorobot potential ranges from cancer diagnosis and drug delivery to tissue repair and more. A major hurdle to these endeavors, however, is finding a way to cheaply make a propulsion system for these devices. New developments may now propel nanoswimmers from science fiction to reality thanks to unexpected help from bacteria.
An international research team has demonstrated a new technique for plating silica onto flagella, the helix-shaped tails found on many bacteria, to produce nanoscale swimming robots. As reported this week in APL Materials, from AIP Publishing, the group’s biotemplated nanoswimmers spin their flagella thanks to rotating magnetic fields and can perform nearly as well as living bacteria.
“We have shown for the first time the ability to use bacterial flagella as a template for building inorganic helices,” said MinJun Kim, professor of mechanical engineering, Lyle School of Engineering at Southern Methodist University and one of the authors of the paper. “This is quite a transformative idea and will have a great impact on not only medicine but also other fields.”
Compared to larger forms of aquatic motion, nanoswimming hinges on an understanding of the Reynolds number, the dimensionless quantities that relates fluid velocity, viscosity and the size of objects in the fluid. With a Reynolds number of one-millionth our own, bacteria must use nonreciprocal motion in the near absence of inertial forces. Using helical tails made of a protein called flagellin, many species of bacteria navigate these microscopic conditions with relative ease.
“If we were shrunk down to the size of a bacteria, we would not be able to use the breast stroke to move through water,” Kim said. “If bacteria were the size of us, they could swim 100 meters in about two seconds.”
Other recently developed methods for constructing these helical structures employ complicated top-down approaches, including techniques that involve self-scrolling nanobelts or lasers. The use of this specialized equipment can lead to very high startup costs for building nanorobots.
Instead, Kim’s team used a bottom-up approach, first culturing a strain of Salmonella typhimurium and removing the flagella. They then used alkaline solutions to fix the flagella into their desired shape and pitch, at which point they plated the proteins with silica. After that, nickel was deposited on the silica templates, allowing them to be controlled by magnetic fields.
“One challenge was to make sure we had helices with the same chirality. If you rotate a left-handed helix and a right-handed helix the same way, they will go in different directions,” Kim said.
STEM image of silica templated flagella; scale bar is 1 ?m.
CREDIT: Jamel Ali
The team took their nanorobots for a spin. When exposed to a magnetic field, the nanorobots kept up the pace with their bacterial counterparts and were projected to be able to cover 22 micrometers, more than four times their length, in a second. In addition to this, the team was able to steer the nanoswimmers into figure-eight paths.
While Kim said he sees potential for nonconducting nanoscale helices in the area of targeted cancer therapeutics, he added that with his team’s work, one might plate conductive materials to flagella and produce helical materials for electronics and photonics.
The Latest on: Nanobots
[google_news title=”” keyword=”nanobots” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
- Superspy Science: Scientist debunks some of the weirdest and wackiest plot lines in James Bond blockbusters - including whether being covered in gold paint really will kill youon February 24, 2024 at 5:23 am
MI6 is secretly working on the ultimate biological weapon – tiny programmable devices called 'nanobots' the size of a red blood cell, invisible to the naked eye. The nanobots can be programmed to ...
- The workforce transition and its human tollon February 21, 2024 at 10:23 am
Otherwise the economic transition may be soaked in blood. Some say the past is prologue, yet Dr. Harari argues that although history is important, we have never been here before; the past is not ...
- Self-propelling nanobots shrink bladder tumours in mice by 90%on February 20, 2024 at 4:00 pm
These “nanobots” penetrate the tumour’s extracellular matrix and accumulate within it, enabling the radionuclide therapy to reach its precise target. In a study conducted at the Institute for ...
- Nanobots Self Replicateon February 17, 2024 at 4:00 pm
Hey, what if you could have a factory that makes robots that is run by… robots? This is hardly an original thought, but we are a long way from having an assembly line of C3POs self-replicating.
- Self-propelled nanobots can deliver drugs to bladder, other tumorson January 28, 2024 at 4:00 pm
Researchers from the Institute for Bioengineering of Catalonia (IBEC) and collaborators have successfully treated bladder tumors in mice using urease-powered nanobots. The testing consisted of the ...
- DNA Nanobots Closes Pre-seed Investment Round to Grow BioPharma Partner Programon January 23, 2024 at 4:00 pm
COLUMBUS, Ohio, January 24, 2024--(BUSINESS WIRE)--DNA Nanobots, a leader in the design and delivery of DNA nanoparticles engineered for targeted therapeutics, announced today that it has closed ...
- Seven years to immortality: Futurist Kurzweil promises a brave new world with AI and nanobotson January 20, 2024 at 12:27 pm
This development would trigger other transformations reshaping our world. Kurzweil envisions a future where nanobots circulate in our bloodstream, repairing tissues and directly dispense ...
- Nanobots for bladder cancer treatment, promising high efficacy and targeted deliveryon January 15, 2024 at 4:35 pm
A new study in Nature Nanotechnology explores the potential use of nanobots to enhance the therapeutic efficacy of intravesical treatment of bladder cancer. Study: Urease-powered nanobots for ...
- What are nanobots?on April 3, 2019 at 9:28 am
These nanobots are a reality and are being actively researched and developed. The field of nanorobotics involves the design, creation, and control of these nanoscale programmable molecules.
- Nanobots In Your Brain Could Be The Future Of Learningon December 15, 2014 at 8:40 am
MIT Media Lab founder Nicholas Negroponte predicts that we might learn by injecting nanobots into the bloodstream, altering the brain at the level of the neuron Subscribe to our daily newsletter ...
via Google News and Bing News