Microscopically small submarines that can swim through our blood to clear out clogged arteries or destroy malignant tumors. This concept may sound utopian, but it isn’t. Various micro- and nanomachines have in fact already been developed. In the journal Angewandte Chemie, American researchers have now introduced a new type of machine that finally has enough propulsive power to penetrate tissue and overcome cellular barriers.
Previous approaches suffered from the fact that the tiny machines didn’t have enough power or lacked biocompatibility. A team led by Sadik Esener and Joseph Wang at the University of California, San Diego has now overcome this challenge. Their new type of micromachine owes its amazing power to ultrasound, which explosively vaporizes tiny drops of liquid, accelerating the machines like bullets.
These novel “microbullets” are conical, pointed, gold-coated tubes with dimensions on the micrometer scale. Their interior is additionally coated with a special biocompatible substance that is capable of binding tiny drops of emulsion through electrostatic interactions. The emulsion used is based on biocompatible perfluorocarbon compounds. An additional magnetic component (nickel) ensures that an external magnetic field can be used to direct the tube to the desired location and orientation.
When ultrasound is then directed at this location, the drops are explosively vaporized. Like bullets in a gun barrel, the tubes are pushed forward by the microexplosion. Depending on the dimensions of the tubes, the size and composition of the emulsion drops, and the strength of the ultrasound signal, speeds around 6.3 m/s can be attained. This is about one hundred times faster than previously reported micromachines, and is enough to shoot the tiny bullets into tissues. Because the fuel is “on board”, propulsion is independent of the environment.
There are a wide variety of possible applications: microbullets could be used to drive drugs deep into diseased tissue, shoot genes into cell nuclei for gene therapy, scrape deposits off of arterial walls, shoot antitumor drugs directly into a tumor, or even carry out micro-operations.A first area of application may be local stimulation of the immune system for fighting bladder cancer. In conventional treatment, a weakened form of the bacterium that causes tuberculosis is introduced to the bladder, causing a superficial bladder infection. This activates the immune system, which attacks the tumor cells as well as the tuberculosis bacteria. Instead of this approach, the microbullets could be shot into the bladder wall to initiate the desired inflammatory reaction – without the risks and side effects associated with the bacteria.
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201201902
Joseph Wang | Angewandte Chemie
Further reports about: > Angewandte Chemie > Bullets > Microdroplets > Tissue Engineering > Ultrasound vaporization > biocompatible perfluorocarbon compounds > electrostatic interactions > healing > immune system > magnetic component > micro- and nanomachines > propulsion for therapeutic micromachines > tiny drops > ultrasound signal
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences