Navigation Links
Silica smart bombs deliver knock-out to bacteria
Date:2/25/2008

CHAPEL HILL Bacteria mutate for a living, evading antibiotic drugs while killing tens of thousands of people in the United States each year. But as concern about drug-resistant bacteria grows, one novel approach under way at the University of North Carolina at Chapel Hill seeks to thwart the bug without a drug by taking a cue from nature.

Mark Schoenfisch and his lab of analytical chemists at UNC have created nano-scale scaffolds made of silica and loaded with nitric oxide (NO) an important molecule in mammals that plays a role in regulating blood pressure, neurotransmission and fighting bacterial infections, among other vital functions.

There was evidence that nitric oxide kills bacteria, but the difficult part involved storing it in a manner such that it could be delivered to bacterial cells, said Evan Hetrick, a doctoral student in Schoenfischs lab and lead author on a paper in the February issue of the American Chemical Societys journal ACS Nano.

While the body constantly produces NO, and can ramp up its production to fight infection, sometimes it cant produce enough to mount a sufficient defense. Previous research using small molecules to deliver NO hit roadblocks controlling the release of the compound was difficult and the molecules were potentially toxic to healthy cells in the body.

With silica scaffolds, nitric oxide stores easily and we could very carefully control the release, said Schoenfisch, an associate professor of chemistry in UNCs College of Arts and Sciences.

Schoenfisch, Hetrick and their colleagues tested their silica scaffolds head-to-head with small molecules against the bacteria Pseudomonas aeruginosa, which is commonly found in burn and other wound infections.

NO delivered by both methods completely killed the bacteria. But the silica nanoparticles delivered the NO right to the bacterias doorstep. In contrast, the small molecules released NO indiscriminately, and the concentration of NO is lost as it makes its way toward bacterial cells.

With the silica particles, more NO actually reached the inside of the cells, enhancing the efficacy of the nanoparticles compared to the small molecule. So, the overall amount of NO needed to kill bacteria is much less with silica nanoparticles, Schoenfisch said. And, with small molecules, youre left with potentially toxic byproducts, Schoenfisch said. Using mouse cells, they proved that the silica nanoparticles werent toxic to healthy cells, but the small molecules were.

Schoenfisch has a history of success with NO-releasing materials. His lab has successfully created a variety of coatings for different biomedical applications. Such materials hold promise as anti-infective coatings and as methods to improve the bodys integration of biological implants such as hip or knee joints and implanted sensors that relay various biological measures, such as blood glucose or oxygen concentrations.

The amount and rate of NO release are easily modified and controlled by using these different silica nanoparticles. Release rates are a function of the precursors used to make the nanoparticles, Schoenfisch said. It depends entirely on how we build the silica structures.

Future research will include studying additional bacterial strains, active targeting, preferential uptake and biodistribution studies.


'/>"/>

Contact: Clinton Colmenares
clinton_colmenares@unc.edu
919-843-1991
University of North Carolina at Chapel Hill
Source:Eurekalert

Related medicine news :

1. OSHA Establishes a New National Emphasis Program on Silica
2. New Smart Technology Makes Patient Data Collection Easier, More Efficient
3. New Survey Shows Americans are Still Concerned About Food Safety, Yet Still Not Smart About What They Like to Eat
4. Delta Dental of Illinois Introduces Smile Smart For Your Health
5. Toddler Study Proves Humans Outsmart Apes
6. SMART Association Becomes Healthcare Council Member of Smart Card Alliance
7. Smart insulin nanostructures pass feasibility test, UT study reports
8. New Oral-B(R) Triumph(TM) With SmartGuide(TM) is the First Power Toothbrush With a Wireless Display
9. Pasta Gets Smarter - and Healthier
10. Healthy Living Made Easy with New Diabetes Foodsmart e-Newsletter
11. Oridion Introduces New Smart Capnography System for Improved Patient Safety
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/5/2016)... , ... February 05, 2016 , ... ... setting the stage for new clinical and scientific initiatives have all marked the ... she was appointed President and CEO of the nation’s oldest cancer center, Candace ...
(Date:2/5/2016)... (PRWEB) , ... February 05, 2016 , ... ... College President George H. Van Allen have signed a joint enrollment and degree ... a seamless pathway toward associate and baccalaureate degrees at FHU|Dickson. , The ...
(Date:2/5/2016)... ... 05, 2016 , ... The American public tends to feel uncomfortable about drinking ... regular municipal or well water. The recent experience with lead contaminated water in Flint, ... long way toward increasing public acceptance of recycled waste water as drinking water. ...
(Date:2/5/2016)... ... 05, 2016 , ... At its annual meeting held last week, the American ... National Board of Directors. Mr. McDermott succeeds former APDA Chairman, Fred Greene. , "We ... Chambers , APDA President and CEO. “Pat has tirelessly served APDA since 2001 when ...
(Date:2/5/2016)... ... February 05, 2016 , ... In sleep, when the defenses of the day ... feature of patients with eating disorders is significant self-criticism, and consequently these patients experience ... are regarded as maladaptive means for coping with this unease, but also leads to ...
Breaking Medicine News(10 mins):
(Date:2/5/2016)... CENTENNIAL, Colo. , Feb. 5, 2016  As ... about health. The multitude of recommended screenings and tests ... healthy aging a priority. However, for the majority of ... of proactive health planning. For the 37.5 million American ... time like the present to make hearing health a ...
(Date:2/5/2016)... 2016 Aethlon Medical, Inc. (Nasdaq: AEMD ), ... will be presenting at Source Capital Group,s 2016 Disruptive Growth ... at 2:15 p.m. ET on Wednesday, February 10, 2016.  ... taking place at 3:15 p.m. ET. http://www.aethlonmedical.com .  ... after the conclusion of the live event. The panel discussion ...
(Date:2/5/2016)... 2016  Zimmer Biomet Holdings, Inc. (NYSE and SIX: ... underwritten secondary offering of 11,027,558 shares of its common ... of Blackstone and Goldman Sachs.  The shares are being ... $96.45 per share. The selling stockholders will receive all ... nor any of its directors, officers or other stockholders ...
Breaking Medicine Technology: