Synthetic mini-motor with enormous power developed

Bacteria as a role model: Conversion of chemical energy into rotational energy at the supramolecular level for the first time

· ScienceDaily
Source:Technical University of Munich (TUM)
Summary:Researchers developed an artificial motor at the supramolecular level that can develop impressive power. This wind-up motor is a tiny ribbon made of special molecules. When energy is applied, this ribbon aligns itself, moves like a small fin and can thus push objects. The energy for this comes from a chemical fuel.

Researchers at the Technical University of Munich (TUM) have developed an artificial motor at the supramolecular level that can develop impressive power. This wind-up motor is a tiny ribbon made of special molecules. When energy is applied, this ribbon aligns itself, moves like a small fin and can thus push objects. For the first time, the energy for this comes from a chemical fuel.

Until now, the conversion of chemical energy into rotational energy on a supramolecular level, i.e. for small objects consisting of more than one molecule, was only known from biology. Primitive bacteria, known as archaea, use the chemical fuel ATP to rotate their tiny fin-like locomotion organs, the flagella, and thus move around. Synthetic replicas of this process have not existed until now. In the future, the new development could be used in nanorobots that swim through blood vessels to detect tumor cells, for example.

Chemical fuel drives the rotation

The peptide ribbons developed by a team led by Brigitte and Christine Kriebisch and Job Boekhoven, Professor of Supramolecular Chemistry, are a few micrometers long and just a few nanometers wide. When chemical fuel is added, they gain structure and the ribbons curl up into small tubes, causing them to begin to rotate. This process can even be observed live under the microscope.

The researchers discovered that they can control the rotation speed of the ribbons by the amount of fuel added. In addition, the direction of rotation — clockwise or anti-clockwise — can be influenced by the structure of the molecular building blocks of the ribbons. The research results were published in the journal Chem.

Crawling on surfaces

Together with Prof. Matthias Rief, TUM Professor of Molecular Biophysics, who works on state-of-the-art optical measurement methods, the researchers found that the ribbons exert enough force on their surroundings to move micrometer-sized objects. Determining the force is one of the most important results for practical use.

If several rotating ribbons are brought together at a central point, for example, small "micro-walkers" are created that can crawl along surfaces. In the future, after further improvements, these micro-walkers could possibly be used for medical applications such as transporting drugs in the body. The fuel used is not yet suitable for this, as it would be harmful to the organism.

Related Terms

Renewable energyRenewable energy (sources) or RES capture their energy from existing flows of energy, from on-going natural processes, such as sunshine, wind, flowing water, biological processes, and geothermal heat flows. The most common definition is that renewable energy is from an energy resource that is replaced rapidly by a natural process such as power generated from the sun or from the wind. Most renewable forms of energy, other than geothermal and tidal power, ultimately come from the Sun. Some forms are stored solar energy such as rainfall and wind power which are considered short-term solar-energy storage, whereas the energy in biomass is accumulated over a period of months, as in straw, or through many years as in wood. Capturing renewable energy by plants, animals and humans does not permanently deplete the resource. Fossil fuels, while theoretically renewable on a very long time-scale, are exploited at rates that may deplete these resources in the near future. Renewable energy resources may be used directly, or…EnergyIn general, the word energy refers to a concept that can be paraphrased as "the potential for causing changes", and therefore one can say that energy is the cause of any change.Power stationA power station or power plant is a facility for the generation of electric power. At the centre of nearly all power stations is a generator, a rotating machine that converts mechanical energy into electrical energy by creating relative motion between a magnetic field and a conductor.Energy developmentEnergy development is a field of endeavor focused on making available sufficient primary energy sources and secondary energy forms to meet the needs of society.Potential energyPotential energy is stored energy.Radiant energyRadiant energy is the energy of electromagnetic waves.