On the way to the nanocarrier: Researchers are realizing molecular telegraphy

Nanotechnology is an area in which great strides can still be made. Significant advances have been made in this area in the last few years, but we are still a long way from scientific dreams like nanofactories. One problem with this is that nanomachines are currently difficult to control. Researchers at the University of Graz have now succeeded in transporting a molecule in a targeted manner over a longer distance to a destination.

Nanofactories as a vision of the future

Nanomachines is a technology area that can significantly shape the future. Whether nano cars, miniature motors or tiny medical robots: the possible uses are endless. With the help of the small, molecular robots, even very complex components can be constructed in nano format. Whole factories in small format are also conceivable. A prerequisite for this, however, is to be able to specifically control the nanomachines. This also includes the transport of molecules over a longer distance. One approach is to use a type of nanocarrier to bring the molecules to their destination - a small robot that travels a fixed route and to which the desired molecules can be attached.

However, this is a difficult undertaking, which is mainly due to the proper movement of the molecules and their tendency to react to small disturbances. Up until now, precise control of molecular movements was only possible with the help of atomic tweezers or the tip of a scanning tunneling microscope.

Researchers from Graz move molecules

The experiment of a research team led by Donato Civita from the University of Graz now showed that there is another way. The scientists were able to transport a molecule over a long distance to a predefined destination and back again. The molecule moved back and forth on a layer of silver in a straight line and in a targeted manner between a transmitter and a receiver.

The tip of a scanning tunneling microscope was used as a transporter. These are thread-like molecules made up of three flexibly coupled fluorene units and a bromine atom at each end. In their original form, these molecules are immobile. However, thanks to their dipole properties, they respond to electrical fields.

Molecule migrates along silver atoms

The transmission starts when a scanning tunneling microscope tip rotates the transporter molecule into a predefined orientation, namely parallel to a row of atoms on the silver base. When the transmitter tip creates a repulsive electric field while the more distant receiver tip creates an attractive field the DBTF molecule moves from one tip to the other along the row of silver atoms. Although the surface is atomically flat, the molecules only move in one direction, only along a single row of atoms. During this process we were also able to measure how much time the molecule needed for this and thus determine its speed says Leonhard Grill from the University of Graz, who was involved in the study. The molecules covered distances of up to 150 nanometers at a speed of up to 0.1 millimeters per second.

The researchers method opens up completely new possibilities both in basic research and in the field of nanotechnological applications. By researching the movement of individual molecules we gain insights into the physical and chemical processes that are relevant for the molecular dynamics of chemical reactions says Grill.