Navigation Links
New visible light photocatalyst kills bacteria, even after light turned off

CHAMPAIGN, Ill. In the battle against bacteria, researchers at the University of Illinois have developed a powerful new weapon an enhanced photocatalytic disinfection process that uses visible light to destroy harmful bacteria and viruses, even in the dark.

Based upon a new catalyst, the disinfection process can be used to purify drinking water, sanitize surgical instruments and remove unwanted fingerprints from delicate electrical and optical components.

"The new catalyst also has a unique catalytic memory effect that continues to kill deadly pathogens for up to 24 hours after the light is turned off," said Jian Ku Shang, a professor of materials science and engineering at the U. of I.

Shang is corresponding author of a paper that is scheduled to appear in the Journal of Materials Chemistry, and posted on the journal's Web site.

Shang's research group had previously developed a catalytic material that worked with visible light, instead of the ultraviolet light required by other catalysts. This advance, which was made by doping a titanium-oxide matrix with nitrogen, meant the disinfection process could be activated with sunlight or with standard indoor lighting.

"When visible light strikes this catalyst, electron-hole pairs are produced in the matrix," Shang said. "Many of these electrons and holes quickly recombine, however, severely limiting the effectiveness of the catalyst."

To improve the efficiency of the catalyst, Shang and collaborators at the U. of I. and at the Chinese Academy of Sciences added palladium nanoparticles to the matrix. The palladium nanoparticles trap the electrons, allowing the holes to react with water to produce oxidizing agents, primarily hydroxyl radicals, which kill bacteria and viruses.

When the light is turned off, the palladium nanoparticles slowly release the trapped electrons, which can then react with water to produce additional oxidizing agents.

"In a sense, the material remembers that it was radiated with light," Shang said. "This 'memory effect' can last up to 24 hours."

Although the disinfection efficiency in the dark is not as high as it is in visible light, it enables the continuous operation of a unique, robust catalytic disinfection system driven by solar or other visible light illumination.

In addition to environmental applications, the new catalyst could also be used to remove messy, oily fingerprints from optical surfaces, computer displays and cellphone screens, Shang said.


Contact: James E. Kloeppel
University of Illinois at Urbana-Champaign

Related biology news :

1. Bottom trawling impacts, clearly visible from space
2. Invisible bacteria dupe the human immune system
3. Cataloguing invisible life: Microbe genome emerges from lake sediment
4. Research shows that invisible hand guides evolution of cooperative turn-taking
5. Seeing previously invisible molecules for the first time
6. Clemson scientists shed light on molecules in living cells
7. September Geology and GSA Today media highlights
8. Highlights from the September 2007 Journal of the American Dietetic Association
9. Genome study shines light on genetic link to height
10. Pig study sheds new light on the colonisation of Europe by early farmers
11. Researchers developing device to predict proper light exposure for human health
Post Your Comments:
(Date:8/15/2017)...   ivWatch LLC , a medical device company focused on ... receipt of its ISO 13485 Certification, the global standard for medical ... Standardization (ISO®). ... Continuous Monitoring device for the early detection of IV infiltrations. ... "This is an important milestone for ivWatch, as ...
(Date:6/30/2017)... Va. , June 30, 2017 ... leading developer and supplier of face and eye ... ATA Featured Product provider program. ... an innovative way to monitor a driver,s attentiveness ... greatly from being able to detect fatigue and ...
(Date:6/14/2017)... -- IBM (NYSE: IBM ) is introducing several innovative partner ... developing collaboration between startups and global businesses, taking place in ... event, nine startups will showcase the solutions they have built ... France is one of ... 30 percent increase in the number of startups created between ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... ... will be hosting a Webinar titled, “Pathology is going digital. Is your lab ... digital pathology adoption best practices and how Proscia improves lab economics and realizes ...
(Date:10/11/2017)... ... ... Disappearing forests and increased emissions are the main causes of the evolving air ... living in larger cities are affected by air pollution related diseases. , That is ... globally - decided to take action. , “I knew I had to take action ...
(Date:10/10/2017)... ... , ... San Diego-based team building and cooking events company, Lajollacooks4u, has unveiled ... bold new look is part of a transformation to increase awareness, appeal to new ... , It will also expand its service offering from its signature gourmet cooking classes ...
(Date:10/10/2017)... ... October 10, 2017 , ... Dr. Bob Harman, founder and CEO of ... Club. The event entitled “Stem Cells and Their Regenerative Powers,” was ... Dr. Harman, DVM, MPVM was joined by two human doctors: Peter B. Hanson, M.D., ...
Breaking Biology Technology: