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Dutch researchers manage to capture the movement of bacteria using an extremely sensitive membrane, an advance that they plan to apply to the fight against antibiotic resistance and, later, against cancer
Antibiotic resistance has become one of the great problems in medicine. The infections that many patients suffer during their hospital stays for other pathologies make their recovery difficult or impossible because, despite great advances in the treatment of many diseases, a growing number of people end up dying from superbacteria that current antibiotics are not capable of killing. .
Developing new drugs that eliminate them and raising awareness among the population about the importance of using them correctly and only when they are really necessary are the two pillars to deal with antibiotic resistance.
A team from the Delft University of Technology, in the Netherlands, this week provides a new advance that can help combat this serious health problem and that has graphene and nanotechnology as protagonists. As explained in the magazine Nature Nanotechnology, They have manufactured with this two-dimensional material thin membranes so sensitive that they are capable of detecting the movement of bacteria.so, which is the same, the sound they emit when moving, which they compare to the soundtrack of bacteria.
As Farbod Alijani, the researcher leading this work, explains, ""If we can hear a bacteria we can know if it is alive or dead." When an antibiotic is given to fight an infection, the bacteria die and the sound stops, unless it is resistant to that drug. And that is what they have been able to do in their laboratory: capture the very faint sound of individual bacteria thanks to graphene.
Researchers realized this property while studying the mechanical characteristics of this carbon-based material discovered in 2004 by Konstantin Novoselov and Andre Geim, and dubbed the wonder material because it is transparent, flexible, extraordinarily resistant, abundant, economical and conducts electricity better than any other known metal. Features that made it suitable for a wide variety of potential applications.
They wondered what would happen if this extremely sensitive material came into contact with a living being such as an isolated bacteria, so they began a collaboration with Cees Dekker's nanobiology group and Peter Steeneken's nanomechanics group: "Our experiments were mainly carried out with E. coli, which is the main model bacteria, and its mutant strains that differ in a single gene that affects cell motility [the ability of a cell to move spontaneously and independently]. In addition to E. coli, we also tested bacteria like B. Subtillis, and we detected its sound," details Farbod Alijani via email.
When a single bacteria adheres to the surface of a graphene membrane, it generates random oscillations with very low amplitudes, a few nanometers, which they were able to detect by 'hearing' the sound that that bacteria emits. The experimental results were unambiguous: If the bacteria were resistant to the antibiotic, the oscillations continued at the same level. When they were susceptible to the drug, the vibrations decreased an hour or two later and then disappeared completely.
According to the authors, their research therefore has great implications for the detection of antibiotic resistance. "We are currently evaluating the applicability of this technology against a variety of pathogen samples and antibiotics that act in different ways. Our results (not yet published) are very promising and show that our technology can be applied to a broader range of gram-positive bacteria and negative, including Pseudomonas aeruginosa y Staphylococcus aureus"he points out.
Their goal is to optimize this platform and validate it against a variety of pathogenic samples, so that it can be used as an effective diagnostic toolkit for rapid detection of antibiotic resistance in clinics.
A global threat
What will these tests consist of? Will they do a blood test? "For this, technological advances are still underway in my group. In not too long, I foresee that these experiments will be performed with positive blood cultures, as well as with isolated bacteria. I believe that this technology can change the current paradigm in susceptibility testing. to antibiotics by reducing the time for diagnosis and sensitivity testing of bacterial infections from a few days to a few hours," says the scientist.
In addition to applying this technology to the rapid detection of antibiotic resistance, which Alijani defines as "a global threat," he believes that it can be used "in bacterial infections in general. For example, for sepsis, which requires very rapid detection and the correct administration of antibiotics to save patients' lives. In the longer term, I see the application of the technology going beyond bacterial cells and, for example, it can be applied to cancer cells to test the effectiveness of antimitotic drugs [they block cell growth by preventing mitosis or cell division and for this reason they are used in oncology].
The Dutch researcher continues to believe that graphene is as promising a material as was predicted when it was first synthesized: "When any material is discovered, it takes time to mature it and take it from the laboratory to the factory; and this is what is There are many technological advances, underway not only in my group and for the detection of bacterial nanomovements, but also to manufacture other next generation biosensors and pressure and gas sensors within the EU flagship graphene initiative. , as well as many other research groups around the world," he points out.
Source: The World
