Buckyballs could keep water systems flowing

Buckyball-Treated Membrane
This is a buckyball-treated membrane. Credit: Duke University

Microscopic particles of carbon known as buckyballs may be able to keep the nation's water pipes clear in the same way clot-busting drugs prevent arteries from clogging up.

Engineers at Duke University have found that buckyballs hinder the ability of bacteria and other microorganisms to accumulate on the membranes used to filter water in treatment plants. This attribute leads the researchers to believe that coating pipes and membranes with these nanoparticles may prove to be an effective strategy for addressing one of the major problems and costs of treating water.

"Just as plaque can build up inside arteries and reduce the flow of blood, bacteria and other microorganisms can over time attach and accumulate on water treatment membranes and along water pipes," said So-Ryong Chae, post-doctoral fellow in Duke's environmental and civil engineering department. The results of his experiments were published March 5, 2009 in the Journal of Membrane Sciences.

Membrane Without Buckyball Treatment
This is a membrane without buckyball treatment. Credit: Duke University

"As the bacteria build up on these surfaces, they attract other organic matter, creating a biofilm that slowly builds up over time," Chae continued, "The results of our experiments in the laboratory indicate that buckyballs may be able to prevent this clogging, known as biofouling. The only other options to address biofouling are digging up the pipes and replacing the membranes, which can be expensive and inconvenient."

A buckyball, or C60, is one shape within the family of tiny carbon shapes known as fullerenes. They are named after Richard Buckminster Fuller, the inventor of the geodesic dome, since their shape resembles his famous structure.

"Biofouling is viewed as one of the biggest costs associated with membrane-based water treatment systems," said Claudia Gunsch, assistant professor of civil engineering at Duke's Pratt School of Engineering and senior member of the research team. "These membranes have very small pores, so they can get stopped up quickly. If we could increase the time between membrane replacements by 50 percent, for example, that would be a huge cost savings."

According to Chae, the addition of buckyballs to treatment membranes had a two-fold effect. First, treated membranes showed less bacterial attachment than non-treated membranes. After three days, the membranes treated with buckyballs had on average 20 colony forming units, the method by which bacterial colonies are counted.

"In contrast, the number of bacterial colonies on the untreated membrane was too numerous to count," Chae said.

Chae also found that the presence of the buckyballs inhibited respiration, or the ability of the bacteria to use oxygen to fuel its activities.

"As the concentration of buckyballs increased, so did the inhibition of respiration," Chae said. "This respiratory inhibition and anti-attachment suggests that this nanoparticle may be useful as an anti-fouling agent to prevent the biofouling of membranes or other surfaces."

Gunsch said the mechanisms involved are not well-understood.

Both Gunsch and Chae believe that since buckyballs are one of the most widely used nanoparticles, additional research is needed to determine if they have any detrimental effects on the environment or to humans. This is one of many issues being studied at Duke's Center for Environmental Implications of Nanotechnology.

"We need to figure out how resistant these coatings will be to long-term use," Gunsch said. "If they can indeed prevent fouling, they will last longer. If they slough off over time, we need to know what the effects will be."

The current experiments in the laboratory were conducted with Escherichia coli K12, a strain of the bacteria that is widely used in laboratory experiments.

"We focused on a quite specific microorganism, so the next stage of our research will to see if these nanoparticles will have the same effects on bacteria commonly found in the environment or those in mixed microbial communities," Chae said. "We also plan to build a small-scale version of a treatment plant in the lab to conduct these tests."

Source: Duke University


Explore further

How to make a better water filter? Turn it inside out

Citation: Buckyballs could keep water systems flowing (2009, March 5) retrieved 22 September 2019 from https://phys.org/news/2009-03-buckyballs.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
0 shares

Feedback to editors

User comments

Mar 05, 2009
More 'garbage science'?? I speak of the inclusion of only the 'control' experimental result: the photo of what happens without the buckyballs. Where is the corresponding 'experimental group's photo????
Is half a story better than none? For myself, i'll opt for the 'none' and save myself a lot of time.

Just who at physorg is choosing these articles???

shame.

Mar 05, 2009
It was an article about a "possible application" in the first round of testing. I found the article informative and well within the scope of Physorg's style of reporting.

Mar 05, 2009
What planet did tkjkj come from? I see two photos in the story, one with and one without buckyballs.

Mar 05, 2009
And is the bucky ball treated membrane 500 times as expensive as the untreated membrane? Are Bucky balls safe to drink? some are sure to leak through.

Mar 08, 2009
In response to nkalanaga - Mar 05, 2009:

Obviously the buckyballs can't be completely inert, since they are interfering with bacterial respiration. But if they can harm bacterial cells, then they might harm other cells too, such as OUR cells!

So it must be studied carefully before people put these in our drinking water.

Mar 09, 2009
So it must be studied carefully before people put these in our drinking water.


Hear, hear! There are enough insufficiently tested additives and groundwater contaminants in our drinking supply already.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more