The team of scientists say they have engineered nanoscale particles that add the antimicrobial potency of silver to a core of lignin, derived from plant cells.
The scientists say that their research has produced a more effective, greener and safer nanotechnology anti-bacterial agent that could be adapted to a variety of personal care products, as well as for agricultural applications.
Study based on sliver-ion infused lignin nanoparticles
The research findings have been published in the July 13 edition of Nature Nanotechnology, where lead researcher Orlin Velev underlines how silver-ion infused lignin nanoparticles are coated with a charged polymer layer that causes them to adhere to microbes, effectively killing them.
The research points out that the technology is effective against a range of commonly found bacteria in personal care products, including many harmful micro-organisms that are known to spoil a range of cosmetic and personal care products.
Likewise, the scientists point out that the risk to the environment is minimal because the nanoparticles become depleted of sliver as they attack the bacteria, which means the biocompatible lignin core is then readily disposable.
Concerns over environmental impact of silver nanoparticles
Although silver nanoparticles have featured in research into antimicrobials in the past, one of the reservations has been the potential non-biodegradable residue from the particles, a problem that is addressed with this technology.
"People have been interested in using silver nanoparticles for antimicrobial purposes, but there are lingering concerns about their environmental impact due to the long-term effects of the used metal nanoparticles released in the environment," said Velev, INVISTA Professor of Chemical and Biomolecular Engineering at NC State and the paper's corresponding author.
"We show here an inexpensive and environmentally responsible method to make effective antimicrobials with biomaterial cores."
Focus on food, but wider reach
The preliminary research was carried out on bacterium known to cause food poisoning, which the researchers say the nanoparticles were highly successful against, while the ‘recipe’ for the nanoparticles could be adjusted to attack specific types of bacteria.
"We expect this method to have a broad impact," said Alexander Richter, the paper’s first author and an NC State PhD candidate.
"We may include less of the antimicrobial ingredient without losing effectiveness while at the same time using an inexpensive technique that has a lower environmental burden. We are now working to scale up the process to synthesize the particles under continuous flow conditions."