Engineers from the University of California at San Diego have created a nanoscale fiber with an incredible level of sensitivity: it can capture the vibrations produced by the turbulence created by the moving bacteria, as well as the sound waves created by the beating cells of the heart tissue. In the future, this level of sensitivity will allow specialists to monitor each individual cell and warn about changes in the process of their normal operation.
“This tool can open the door for us to monitor the most subtle interactions and changes in the body, which was simply impossible before,” says Donald Sirbuli, one of the creators of hypersensitive fiber from the University of California.
Progress in the development of microscopy technology allowed us to penetrate into the tiniest crevices of our physical world, but in order to really understand what is happening in this world, it is not enough just to be able to see it – one must also have the opportunity to feel it.
It should be noted that microscopes capable of monitoring the tiniest forces already exist. One example is at least an atomic force microscope capable of not only scanning the behavior of atoms, but also manipulating them. However, the method according to which such microscopes work does not allow them to be used for the study of biological systems.
The ability to measure the biological forces of the smallest scales requires scientists to use a new approach. Therefore, a group of specialists from the United States has developed from tin oxide fiber, which is 100 times thinner than a human hair. To give the optical fiber the ability to “feel”, tin oxide was coated with a thin layer of polymer, studded with gold nanoparticles.
How it works
The method of using such a fiber is very simple. All you need is to place the optical fiber in a solution containing cells or bacteria. The optical fiber emits light that interacts with gold particles. Biological forces of the body and the sound waves they create collide with gold nanoparticles, slightly pressing them into the polymer shell. With this, you can calculate both the level of the force itself and the level of sound it creates. The creators of the fiber checked his work by observing the cells of the beating heart, as well as the movement of flagella (driving organs) of bacteria.
“With the help of this device, we were able not only to catch these barely noticeable biosiles and sounds, but also carried out their quantitative assessment. This tool is ideally suited for high-resolution nanomechanical sounding, “Sirbuli comments.
After calibrating the device it turned out that such fiber can be 10 times more sensitive than atomic force microscopes and is capable of detecting biological forces with a level of exposure of less than 160 fN (femtemecu), and of sound less than -30 dB (decibel). And this, in turn, is a thousand times less than the level that can be perceived by the human ear.
Specialists note that with the use of different types of polymer coating, it is possible to expand the range of efficiency of the optical fiber that they have created. For example, to measure greater forces, a more durable polymer coating can be used, and to determine lower forces-with a fiber, a very soft coating, like the same hydrogel, can be used.
In the future, researchers plan to use optical nanofibers to measure the bioactivity and mechanical behavior of individual cells. This will further enhance the capabilities of technology and, in the long run, can lead to the creation of supersensitive biosteoscopes.
