Ithaca, N.Y. – Scientists in the U.S. may have found a way to keep bacteria from sticking around, so to speak.
Scientists at Cornell University and Rensselaer Polytechnic Institute have developed a new type of nanoscale surface that bacteria can’t stick to, reports the Cornell Chronicle. The technology, say the
Nanoporous alumina repels E. coli cells. From the Cornell Chronicle.
authors, holds promise for the food processing industry, among several others.
The scientists explain that 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.
These pores can be as small as 15 nanometres; a sheet of paper is about 100,000 nanometers thick.
When the anodization process was applied to aluminum, it created a nanoporous surface called alumina, which proved effective in preventing surrogates of two well-known pathogens, Escherichia coli O157:H7 and Listeria monocytogenes, from attaching, says the Cornell Chronicle. The study was recently published in the journal Biofouling. The study also investigates how the size of the nanopores changes the repulsive forces on bacteria.
The paper’s senior author, Carmen Moraru, associate professor of food science, told the website that the technology “is probably one of the lowest-cost possibilities to manufacturer a nanostructure on a metallic surface.”
Finding low-cost solutions to help limit bacterial attachment is key in food processing applications. Says Moraru “The food industry makes products with low-profit margins. Unless a technology is affordable it doesn’t stand the chance of being practically applied.”
Other strategies for limiting bacterial attachment have limited applications – especially when it comes to food processing. With food processing, surfaces must meet food safety guidelines and be inert to food that they may contact.
The scientists say that future work will investigate the repulsive effect of these surfaces on other bacteria, and the use of other anodized materials for this purpose.
Photo by Guoping Feng; from the Cornell Chronicle website