Specialists of the AgriLife Research company which is subsidiary of the Texas university A&M and their colleagues from university of Florida developed a biosensor of new type which can find the fact of presence of bacteria of a type of a listeriya (listeria) at the analyzed samples. Thus, the sensor finds absolutely insignificant concentration of bacterial infection and does it within two-three minutes, practically, in real time.
“In the near future we will bring sensitivity of our sensor to such level that he will be able to find single bacteria in a sample of material, weighing 25 grams” – doctor Carmen Gomes (Dr tells. Carmen Gomes), the leading researcher of the AgriLife Research company, – “Besides, just the same technology can be used for detection of other pathogenic organisms, for example E. Coli. But listeriya were chosen as a starting point because of their firmness and ability to survive even at very low temperatures. It is one of the most widespread species of microorganisms striking foodstuff and the reason of the third part of fatal cases from food poisonings”.
Now detection of pathogenic bacteria of a type of listeriya in foodstuff demands work of the highly skilled personnel working in specially equipped laboratories. And processes of identification of bacteria can go till some days. Therefore often it happens that due to the lack of express analysis methods the products infected with listeriya get on the consumer market.
The biosensor created by scientists for the present is in a stage of experimental development, but the ready portable device created on its basis can appear in the near future. And most that there is attractive in this case, it that people with the lowest skill level will be able to use such device even.
Despite ordinary-looking appearance the sensor is very difficult device consisting of a basis, electrodes, the nanostructured surface on which the active biological components capable to react on bacteria of a certain look settle down. These biological components represent the person elements of one-chained DNA or a molecule of RNA which contact the receptors which are on outer side of a cellular membrane of a pathogenic microorganism. Such connection can be compared to how the key of a certain exotic form can enter only the keyhole intended for it.
The idea of realization of such “binding” was borrowed by scientists in wildlife. The squid of a type of Euprymna scolopes (Hawaiian bobtail squid), the sea being forming symbiotic relationship with bioluminescent bacteria by means of the similar mechanism became a prototype. On a body of a squid there are microscopic “hair” which choose and take only bacteria of a certain view from all variety of the microorganisms living in the ocean.
Now the created biosensor has the size, are comparable to the stamp size, only two wires attached to certain places of its active zone depart from it. Within several minutes when polymeric “hair” on a surface of the sensor take bacteria of a certain look, sensor resistance sharply changes that is rather simply measured by traditional electronic methods.
It is necessary to notice that at some modification such sensors can be connected to chains of smartphones and portable computers. And the paper disposable biosensor developed now, will be very cheap in production, it will be possible to get rid of it without effort after its use.