January 16, 2015 at 6:26 pm #2756
BACTERIA CANT CLING TO REPULSIVE NEW SURFACE
Posted by Krishna Ramanujan-Cornell on January 15, 2015
Bacteria cant stick to a new type of nanoscale surface that could prove useful in food processing, medical, and shipping industries.
The technology uses an electrochemical process called anodization to create nanoscale pores that change the electrical charge and surface energy of a metal surface, which in turn exerts a repulsive force on bacterial cells and prevents attachment and biofilm formation.
Whereas a sheet of paper is about 100,000 nanometers thick, these pores can be as small as just 15 nanometers.
When the researchers applied the anodization process to aluminum, it created a nanoporous surface called alumina, which proved effective in preventing surrogates of two well-known pathogens, O157:H7 and , from attaching, according to the study in .
The study also investigates how the size of the nanopores changes the repulsive forces on bacteria.
A CHEAPER WAY TO FIGHT BIOFILMS
Its probably one of the lowest-cost possibilities to manufacture a nanostructure on a metallic surface, says senior author Carmen Moraru, associate professor of food science at Cornell University. Guoping Feng, a research associate in Morarus lab, is the papers first author.
Finding low-cost solutions to limiting bacterial attachments is key, especially in biomedical and food processing applications. The food industry makes products with low profit margins, says Moraru. Unless a technology is affordable it doesnt stand the chance of being practically applied.
Anodized metals could be used to prevent buildups of biofilmsslick communities of bacteria that adhere to surfaces and are tricky to removein biomedical clean rooms and in equipment parts that are hard to reach or clean, Moraru says.
There are other strategies for limiting bacterial attachment to surfaces, including chemicals and bactericides, but these have limited applications, especially when it comes to food processing, Moraru says. With food processing, surfaces must meet food safety guidelines and be inert to food that they may contact.
Anodized metal could also have marine applications, such as keeping ship hulls free of algae.
Future work will investigate the repulsive effect of these surfaces on other bacteria, and the use of other anodized materials for this purpose.
The collaborating group from Rensselaer Polytechnic Institute is led by Diana Borca-Tasciuc, associate professor of mechanical, aerospace, and nuclear engineering.
The US Department of Agriculture funded the work.
Cornell University [/I]
You must be logged in to reply to this topic.