Dr Serge Cosnier alongwith his team at Joseph Fouried University of Grenoble have created a biofuel cell which generates electricity using the glucose and oxygen at concentrations found in the body of a living animal.It is said within next couple of decades biofuel cell may be used to power many medical implants (including sensors and artificial organs). To power them up you will need to take just one can of coke.
Many artifical organs including bladder, hearts, and kidneys are under development these days.They all will need electricity to run. Batteries are good source but they have many limitations. Even the low power devices like pacemaker,which rely on batteries have fixed lifespan. Studies show that among 70 years old persons, pacemaker was implanted in one in five persons and they lived for another 20 years on the average. So they needed three operations just to replace the battery and each operations has complications of surgery. On the other hand kidneys, eyes etc would have high energy demands so user will have to change the power source after every few weeks. So it is practically infeasible to use batteries with such devices.
Biofuel cells are simply made up of two special electrodes. One has ability to remove electrons from glucose and the other has ability to donate electrons to molecules of oxygen and hydrogen producing water. If these electrodes are inserted into a solution containing glucose and oxygen, one will take electrons from the glucose and other will start to dump them into oxygen. Connecting these electrodes to a circuit will result in electric current. Dr Cosnier says that a battery consumes the stored current and stops working when current is finished. As biofuel consumes glucose and oxygen found in the body, so theoretically it will keep on working for ever.
In 2002, Mr Itamar Willner a researcher at Hebrew University in Jerusalem, speculated in his article in prestigious journal of science that using techniques of biotechnology the artificial organs can be powered by biofuel cells. As a result of this article,biofuel cells have received alot of attention.
Enzymes are special biological molecules which accelerate chemical reactions. Research has shown that an enzyme known as glucose oxidase is very good to remove electrons from glucose. So, during last decade there has been a lot of research in the world to produce electricity from enzyme.
Dr Cosnier alongwith his team used all of the last decade research to design their device. It was a small device having size that of a grain of rice.To create one electrode glucose oxidase was mixed with a paste of carbon nanotubes, and to prepare the other electrode glucose and polyphenol oxidase were mixed. Each of the lectrodes had platinum wire, that was responsible for carrying current to the circuit. A special material was used to wrap electrodes. The purpose was to to prevent the enzymes or nanotubes from escaping into the body of the animal. Then, a mesh was used to wrap the whole system to protect the electrodes from the immune system of the body. The glucose and oxygen could easily flow to the electrodes.
Then this system was implanted in the body of a rat and tested for 40 days. Neither any side effects nor any behavioral change was observed. However, due to very small size of rats very low power was generated.
Dr Cosnier's next plan is to implant the fuel cell in a cow and he expects to generate enough energy in this way. He thinks it can be enough to power a transmitter to control sensors inside the cow.
During next decade, Prof Willner expects the use of biofuel cells in laptops and mobile phones. However, still a lot of work needs to be done.
No comments:
Post a Comment