Normal Light Can Now Be Used To Kill Bacteria
Bacteria are tiny living organisms all around us. Though some of them are useful, the rest cause harm to human interests in more than one ways. Disinfectants are the substances used to kill the harmful bacteria. But over the years the bacteria are found to be more and more resistant to the disinfectants. As a result of this, researchers were in the look out for an effective, all purpose and easily applicable disinfectant for quite for time.
Recently, a German research group found a powerful chemical disinfectant which can kill all the infection causing germs in the surgical instruments. Now researchers from University of Illinois have developed yet another potent disinfectant which can kill bacteria and viruses by using normal light.
The new disinfectant has a new feature. It has the ability to kill the germs for 24 hours, even after the used light is turned off. This makes the disinfectant effective even in dark. The disinfectant is a powder and can be used for purifying drinking water and for removing fingerprint marks from optical and electrical devices, apart from cleaning surgical instruments.
According to researcher Jian Ku Shang, Professor of Material Science, University of Illinois, when normal light falls on this powder, a pair of electron and hole is formed. Earlier these particles used to recombine soon after their formation. This made the powder less effective. To address this problem, researchers added a new substance called palladium nano particles, to the main mixture of titanium-oxide and nitrogen.
Now when light falls on the main mixture and electron-hole pair is formed, the palladium nanoparticles get hold of the electrons. This allows another component the holes to interact with water. This produces chemical substances called oxidizing agents. These agents kill the germs.
When the light is switched off, the palladium nanoparticles release the held electrons slowly. Now these released electrons interact with water to produce oxidizing agents for killing germs. The palladium nanoparticles work for a period of 24 hours when they were illuminated with light. During these 24 hours, if the light is switched off, they release the held electrons making the disinfectant powder effective even in darkness.