Express diagnostics: imitating nature
Quick and easy-to-use diagnostic tests have been created
Roman Ivanov, Computer
Mimicking natural recognition mechanisms, bioengineers from the University of California at Santa Barbara (USA) and the University of Rome "Tor Vergata" (Italy) have developed inexpensive medical diagnostic tests that can give results in a few minutes. Scientists hope that their technology will shake up the entire global healthcare system, since its next step should be the creation of simple devices available for use in any places of medical care, diagnosis of venereal, allergic, autoimmune and other diseases
The presented technology is based on the use of nanometer-sized molecular DNA switches capable of detecting the presence of specific antibodies for a wide range of diseases. The details of the study are described in the Journal of the American Chemical Society (Ricci et al., Rational Design of Allosteric Inhibitors and Activators Using the Population-Shift Model: In Vitro Validation and Application to an Artificial Biosensor).
Modern diagnostic tests are extremely powerful, but one drawback can negate all the advantages: most of these methods require complex, cumbersome, very expensive equipment. Patients have been waiting for days or even weeks for the results of most tests for sexually transmitted diseases. The blood sample must be carefully transported to a remote laboratory for analysis by specially trained personnel (there is one laboratory, and there are many medical institutions of different caliber), and only then, in compliance with the general queue, the result will be sent to the attending physician. And now imagine that the analysis is carried out right at the place of blood donation: this will not only reduce the waiting time, but also reduce the risk of spreading infections.
The beginning of the research was... observation of nature. All living beings, from bacteria to humans, collect information about the environment using amazing "molecular nanoswitches" that signal specific molecules by changing their structure. For example, millions of receptor proteins are located on the surface of our cells, designed to detect the presence of various signaling molecules, moving from an inactive state (off) to an active one (on). A special advantage of such switches is their ability to operate in very difficult conditions, such as blood flow.
An electrochemical DNA switch detects the presence of an antibody. Binding to the antibody causes the switch to open, removing the signal element (a bright circle) away from the surface of the electrode and causing the signal to appear. (Fig. UCSB.)
That's how, looking back at nature, scientists have built their artificial molecular switches based on DNA molecules that signal their current state through a change in electric current. The latter is fixed by very inexpensive electronics, similar to the one used in home blood sugar level meters. The use of "nature-spied" nanoswitches made it possible to detect HIV antibodies in a blood sample in less than five minutes. Doesn't this speak to the potential of such diagnostic technology?
According to the authors of the development, the main advantage of electrochemical DNA nanoswitches that diagnose AIDS is that their principle of operation can be easily extended to other diseases, and from here it is close to inexpensive devices for determining dozens of biomarkers of diseases in a very short time and right in the doctor's office (or even at home).
Prepared based on the materials of the University of California at Santa Barbara:
Bioengineers at UCSB Design Rapid Diagnostic Tests Inspired by Nature.
Portal "Eternal youth" http://vechnayamolodost.ru01.10.2012