Cytobots – cyborg bacteria
Graphene helped bioengineers create the world's first "robocop– bacterium
For the first time, an international group of biotechnologists was able to attach a nanodevice to a bacterium and make them work together, turning the microbe into a kind of primitive "cyborg" capable of conducting the simplest scientific research, according to an article published in the journal Scientific Reports (Sreeprasad et al., Graphene Quantum Dots Interfaced with Single Bacterial Spore for Bio-Electromechanical Devices: A Graphene Cytobot, publicly available – VM).
"This is really an amazing device. Look, we have living cells in the form of spores. We assembled a sensor on their surface, and these bacteria played a very important role in the operation of the device. Moreover, their biological component was the part of the sensor that was responsible for responding to stimuli and providing information," explained Vikas Berry from the University of Illinois at Chicago (USA).
Berry and his colleagues named their invention the word NERD (English "nerd"), which in abbreviation means nano-electronic robot device (Nano-Electro-Robotic Device – VM). At its core, it is a "sleeping" bacterium, which scientists have forced to play the role of an ultra-sensitive humidity sensor using a number of nanostructures placed on its surface.
"We took a bacterial spore, and glued a set of graphene-based quantum dots to its shell, and then attached electrodes to each side of the microbe. Then we started to change the degree of humidity in the vicinity of the bacterium. The reaction of the device was lightning fast," the scientist continues.
A drawing from the University of Illinois press release “Tiny bio-robot is a germ suited-up with graphene quantum dots” - VM.
The operation of this sensor is based on one simple fact – the hard shell of bacterial spores is extremely sensitive to the presence of water molecules, and noticeably expands with an increase in the concentration of water vapor in the air or water droplets in its vicinity.
The expansion of the microbe shell leads to a change in the electrical conductivity of graphene strips and electrodes, which is why quantum dots - microscopic light sources – will shine noticeably brighter or dimmer.
According to Berry, their cyber-bacteria reacted to the slightest changes in humidity about 10 times faster than the most sensitive sensors based on polymer materials do. Such bacteria-"cytobots", as scientists note, can be used even in a vacuum, which will allow using sensors based on them to track air leaks and other vital things on the ISS or spacecraft.
Portal "Eternal youth" http://vechnayamolodost.ru25.03.2015