Tag Archives: Frank Gu

Understanding nanotechnology with Timbits; a peculiarly Canadian explanation

For the uninitiated, Timbits are also known as donut holes. Tim Hortons, founded by ex-National Hockey League player Tim Horton who has since deceased, has taken hold in the Canada’s language and culture such that one of our scientists trying to to explain nanotechnology thought it would be best understood in terms of Timbits. From a Jan. 14, 2017 article (How nanotechnology could change our lives) by Vanessa Lu for thestar.com,

The future is all in the tiny.

Known as nanoparticles, these are the tiniest particles, so small that we can’t see them or even imagine how small they are.

University of Waterloo’s Frank Gu paints a picture of their scale.

“Take a Timbit and start slicing it into smaller and smaller pieces, so small that every Canadian — about 35 million of us — can hold a piece of the treat,” he said. “And those tiny pieces are still a little bigger than a nanoparticle.”

For years, consumers have seen the benefits of nanotechnology in everything from shrinking cellphones to ultrathin televisions. Apple’s iPhones have become more powerful as they have become smaller — where a chip now holds billions of transistors.

“As you go smaller, it creates less footprint and more power,” said Gu, who holds the Canada research chair in advanced targeted delivery systems. “FaceTime, Skype — they are all powered by nanotechnology, with their retina display.”

Lu wrote a second January 14, 2017 article (Researchers developing nanoparticles to purify water) for thestar.com,

When scientists go with their gut or act on a hunch, it can pay off.

For Tim Leshuk, a PhD student in nanotechnology at the University of Waterloo, he knew it was a long shot.

Leshuk had been working with Frank Gu, who leads a nanotechnology research group, on using tiny nanoparticles that have been tweaked with certain properties to purify contaminated water.

Leshuk was working on the process, treating dirty water such as that found in Alberta’s oilsands, with the nanoparticles combined with ultraviolet light. He wondered what might happen if exposed to actual sunlight.

“I didn’t have high hopes,” he said. “For the heck of it, I took some beakers out and put them on the roof. And when I came back, it was far more effective that we had seen with regular UV light.

“It was high-fives all around,” Leshuk said. “It’s not like a Brita filter or a sponge that just soaks up pollutants. It completely breaks them down.”

Things are accelerating quickly, with a spinoff company now formally created called H2nanO, with more ongoing tests scheduled. The research has drawn attention from oilsands companies, and [a] large pre-pilot project to be funded by the Canadian Oil Sands Innovation Alliance is due to get under way soon.

The excitement comes because it’s an entirely green process, converting solar energy for cleanup, and the nanoparticle material is reuseable, over and over.

It’s good to see a couple of articles about nanotechnology. The work by Tim Leshuk was highlighted here in a Dec. 1, 2015 posting titled:  New photocatalytic approach to cleaning wastewater from oil sands. I see the company wasn’t mentioned in the posting so, it must be new; you can find H2nanO here.

Discussion of a divisive topic: the Oilsands

As for the oilsands, it’s been an interesting few days with the Prime Minister’s (Justin Trudeau) suggestion that dependence would be phased out causing a furor of sorts. From a Jan. 13, 2017 article by James Wood for the Calgary Herald,

Prime Minister Justin Trudeau’s musings about phasing out the oilsands Friday [Jan. 13, 2017] were met with a barrage of criticism from Alberta’s conservative politicians and a pledge from Premier Rachel Notley that the province’s energy industry was “not going anywhere, any time soon.”

Asked at a town hall event in Peterborough [Ontario] about the federal government’s recent approval of Kinder Morgan’s Trans Mountain pipeline expansion, Trudeau reiterated his longstanding remarks that he is attempting to balance economic and environmental concerns.

“We can’t shut down the oilsands tomorrow. We need to phase them out. We need to manage the transition off of our dependence on fossil fuels but it’s going to take time and in the meantime we have to manage that transition,” he added.

Northern Alberta’s oilsands are a prime target for environmentalists because of their significant output of greenhouse gas emissions linked to global climate change.

Trudeau, who will be in Calgary for a cabinet retreat on Jan. 23 and 24 [2017], also said again that it is the responsibility of the national government to get Canadian resources to market.

Meanwhile, Jane Fonda, Hollywood actress, weighed in on the issue of the Alberta oilsands with this (from a Jan. 11, 2017 article by Tristan Hopper for the National Post),

Fort McMurrayites might have assumed the celebrity visits would stop after the city was swept first by recession, and then by wildfire.

Or when the provincial government introduced a carbon tax and started phasing out coal.

And surely, with Donald Trump in the White House, even the oiliest corner of Canada would shift to the activist back burner.

But no; here comes Jane Fonda.

“We don’t need new pipelines,” she told a Wednesday [Jan. 11, 2017] press conference at the University of Alberta where she also dismissed Prime Minister Justin Trudeau as a “good-looking Liberal” who couldn’t be trusted.

Saying that her voice was joined with the “Indigenous people of Canada,” Fonda explained her trip to Alberta by saying “when you’re famous you can help amplify the voices of people that can’t necessarily get a lot of press people to come out.”

Fonda is in Alberta at the invitation of Greenpeace, which has brought her here in support of the Treaty Alliance Against Tar Sands Expansion — a group of Canadian First Nations and U.S. tribes opposed to new pipelines to the Athabasca oilsands.

Appearing alongside Fonda, at a table with a sign reading “Respect Indigenous Decisions,” was Grand Chief Stewart Phillip, who, as leader of the Union of B.C. Indian Chiefs, has led anti-pipeline protests and litigation in British Columbia.

“The future is going to be incredibly litigious,” he said in reference to the approved expansion of the Trans-Mountain pipeline.

The event also included Grand Chief Derek Nepinak of the Assembly of Manitoba Chiefs, which is leading a legal challenge to federal approval of the Line 3 pipeline.

Although much of Athabasca’s oil production now comes from “steam-assisted gravity drainage” projects that requires minimal surface disturbance, on Tuesday Fonda took the requisite helicopter tour of a Fort McMurray-area open pit mine.

As you can see, there are not going to be any easy answers.

New photocatalytic approach to cleaning wastewater from oil sands

With oil sands in the title, this story had to mention the Canadian province of Alberta, which has been widely castigated and applauded for its oil extraction efforts in their massive oil sands field. A Nov. 24, 2015 news item on Nanotechnology Now describes a new technology for cleaning the wastewater from oil sands extraction processes,

Researchers have developed a process to remove contaminants from oil sands wastewater using only sunlight and nanoparticles that is more effective and inexpensive than conventional treatment methods.

Frank Gu, a professor in the Faculty of Engineering at the University of Waterloo [in the province of Ontario] and Canada Research Chair in Nanotechnology Engineering, is the senior researcher on the team that was the first to find that photocatalysis — a chemical reaction that involves the absorption of light by nanoparticles — can completely eliminate naphthenic acids in oil sands wastewater, and within hours. Naphthenic acids pose a threat to ecology and human health. Water in tailing ponds left to biodegrade naturally in the environment still contains these contaminants decades later.

A Nov. 23, 2015 University of Waterloo news release, which originated the news item, expands on the theme but doesn’t provide much in the way of technical detail,

“With about a billion tonnes of water stored in ponds in Alberta, removing naphthenic acids is one of the largest environmental challenges in Canada,” said Tim Leshuk, a PhD candidate in chemical engineering at Waterloo. He is the lead author of this paper and a recipient of the prestigious Vanier Canada Graduate Scholarship. “Conventional treatments people have tried either haven’t worked, or if they have worked, they’ve been far too impractical or expensive to solve the size of the problem.  Waterloo’s technology is the first step of what looks like a very practical and green treatment method.”

Unlike treating polluted water with chlorine or membrane filtering, the Waterloo technology is energy-efficient and relatively inexpensive. Nanoparticles become extremely reactive when exposed to sunlight and break down the persistent pollutants in their individual atoms, completely removing them from the water. This treatment depends on only sunlight for energy, and the nanoparticles can be recovered and reused indefinitely.

Next steps for the Waterloo research include ensuring that the treated water meets all of the objectives Canadian environmental legislation and regulations required to ensure it can be safely discharged from sources larger than the samples, such as tailing ponds.

Here’s a link to and a citation for the paper,

Solar photocatalytic degradation of naphthenic acids in oil sands process-affected water by Tim Leshuk, Timothy Wong, Stuart Linley, Kerry M. Peru, John V. Headley, Frank Gu. Chemosphere Volume 144, February 2016, Pages 1854–1861 doi:10.1016/j.chemosphere.2015.10.073

This paper is behind a paywall.

Nanomaterials and UV (ultraviolet) light for environmental cleanups

I think this is the first time I’ve seen anything about a technology that removes toxic materials from both water and soil; it’s usually one or the other. A July 22, 2015 news item on Nanowerk makes the announcement (Note: A link has been removed),

Many human-made pollutants in the environment resist degradation through natural processes, and disrupt hormonal and other systems in mammals and other animals. Removing these toxic materials — which include pesticides and endocrine disruptors such as bisphenol A (BPA) — with existing methods is often expensive and time-consuming.

In a new paper published this week in Nature Communications (“Nanoparticles with photoinduced precipitation for the extraction of pollutants from water and soil”), researchers from MIT [Massachusetts Institute of Technology] and the Federal University of Goiás in Brazil demonstrate a novel method for using nanoparticles and ultraviolet (UV) light to quickly isolate and extract a variety of contaminants from soil and water.

A July 21, 2015 MIT news release by Jonathan Mingle, which originated the news item, describes the inspiration and the research in more detail,

Ferdinand Brandl and Nicolas Bertrand, the two lead authors, are former postdocs in the laboratory of Robert Langer, the David H. Koch Institute Professor at MIT’s Koch Institute for Integrative Cancer Research. (Eliana Martins Lima, of the Federal University of Goiás, is the other co-author.) Both Brandl and Bertrand are trained as pharmacists, and describe their discovery as a happy accident: They initially sought to develop nanoparticles that could be used to deliver drugs to cancer cells.

Brandl had previously synthesized polymers that could be cleaved apart by exposure to UV light. But he and Bertrand came to question their suitability for drug delivery, since UV light can be damaging to tissue and cells, and doesn’t penetrate through the skin. When they learned that UV light was used to disinfect water in certain treatment plants, they began to ask a different question.

“We thought if they are already using UV light, maybe they could use our particles as well,” Brandl says. “Then we came up with the idea to use our particles to remove toxic chemicals, pollutants, or hormones from water, because we saw that the particles aggregate once you irradiate them with UV light.”

A trap for ‘water-fearing’ pollution

The researchers synthesized polymers from polyethylene glycol, a widely used compound found in laxatives, toothpaste, and eye drops and approved by the Food and Drug Administration as a food additive, and polylactic acid, a biodegradable plastic used in compostable cups and glassware.

Nanoparticles made from these polymers have a hydrophobic core and a hydrophilic shell. Due to molecular-scale forces, in a solution hydrophobic pollutant molecules move toward the hydrophobic nanoparticles, and adsorb onto their surface, where they effectively become “trapped.” This same phenomenon is at work when spaghetti sauce stains the surface of plastic containers, turning them red: In that case, both the plastic and the oil-based sauce are hydrophobic and interact together.

If left alone, these nanomaterials would remain suspended and dispersed evenly in water. But when exposed to UV light, the stabilizing outer shell of the particles is shed, and — now “enriched” by the pollutants — they form larger aggregates that can then be removed through filtration, sedimentation, or other methods.

The researchers used the method to extract phthalates, hormone-disrupting chemicals used to soften plastics, from wastewater; BPA, another endocrine-disrupting synthetic compound widely used in plastic bottles and other resinous consumer goods, from thermal printing paper samples; and polycyclic aromatic hydrocarbons, carcinogenic compounds formed from incomplete combustion of fuels, from contaminated soil.

The process is irreversible and the polymers are biodegradable, minimizing the risks of leaving toxic secondary products to persist in, say, a body of water. “Once they switch to this macro situation where they’re big clumps,” Bertrand says, “you won’t be able to bring them back to the nano state again.”

The fundamental breakthrough, according to the researchers, was confirming that small molecules do indeed adsorb passively onto the surface of nanoparticles.

“To the best of our knowledge, it is the first time that the interactions of small molecules with pre-formed nanoparticles can be directly measured,” they write in Nature Communications.

Nano cleansing

Even more exciting, they say, is the wide range of potential uses, from environmental remediation to medical analysis.

The polymers are synthesized at room temperature, and don’t need to be specially prepared to target specific compounds; they are broadly applicable to all kinds of hydrophobic chemicals and molecules.

“The interactions we exploit to remove the pollutants are non-specific,” Brandl says. “We can remove hormones, BPA, and pesticides that are all present in the same sample, and we can do this in one step.”

And the nanoparticles’ high surface-area-to-volume ratio means that only a small amount is needed to remove a relatively large quantity of pollutants. The technique could thus offer potential for the cost-effective cleanup of contaminated water and soil on a wider scale.

“From the applied perspective, we showed in a system that the adsorption of small molecules on the surface of the nanoparticles can be used for extraction of any kind,” Bertrand says. “It opens the door for many other applications down the line.”

This approach could possibly be further developed, he speculates, to replace the widespread use of organic solvents for everything from decaffeinating coffee to making paint thinners. Bertrand cites DDT, banned for use as a pesticide in the U.S. since 1972 but still widely used in other parts of the world, as another example of a persistent pollutant that could potentially be remediated using these nanomaterials. “And for analytical applications where you don’t need as much volume to purify or concentrate, this might be interesting,” Bertrand says, offering the example of a cheap testing kit for urine analysis of medical patients.

The study also suggests the broader potential for adapting nanoscale drug-delivery techniques developed for use in environmental remediation.

“That we can apply some of the highly sophisticated, high-precision tools developed for the pharmaceutical industry, and now look at the use of these technologies in broader terms, is phenomenal,” says Frank Gu, an assistant professor of chemical engineering at the University of Waterloo in Canada, and an expert in nanoengineering for health care and medical applications.

“When you think about field deployment, that’s far down the road, but this paper offers a really exciting opportunity to crack a problem that is persistently present,” says Gu, who was not involved in the research. “If you take the normal conventional civil engineering or chemical engineering approach to treating it, it just won’t touch it. That’s where the most exciting part is.”

The researchers have made this illustration of their work available,

Nanoparticles that lose their stability upon irradiation with light have been designed to extract endocrine disruptors, pesticides, and other contaminants from water and soils. The system exploits the large surface-to-volume ratio of nanoparticles, while the photoinduced precipitation ensures nanomaterials are not released in the environment. Image: Nicolas Bertrand Courtesy: MIT

Nanoparticles that lose their stability upon irradiation with light have been designed to extract endocrine disruptors, pesticides, and other contaminants from water and soils. The system exploits the large surface-to-volume ratio of nanoparticles, while the photoinduced precipitation ensures nanomaterials are not released in the environment.
Image: Nicolas Bertrand Courtesy: MIT

Here’s a link to and a citation for the paper,

Nanoparticles with photoinduced precipitation for the extraction of pollutants from water and soil by Ferdinand Brandl, Nicolas Bertrand, Eliana Martins Lima & Robert Langer. Nature Communications 6, Article number: 7765 doi:10.1038/ncomms8765 Published 21 July 2015

This paper is open access.

First ever Nanoscience and Nanotechnology Symposium in English-speaking Caribbean

A July 12, 2014 news item on Nanowerk heralds this new International symposium on nanoscience and nanotechnology,

The ‘International Symposium on Nanoscience and Nanotechnology’ will be hosted at The University of the West Indies (UWI), St. Augustine [in Trinidad and Tobago], from July 15-17, 2014. The symposium, focused on the frontier areas of science, medicine and technology, is the first of its kind in the English-speaking Caribbean and is organised jointly by CARISCIENCE, The UWI and the University of Trinidad and Tobago. The symposium consists of a Public Lecture on Day 1 and Scientific Sessions over Days 2 and 3.

This international symposium is important and ground-breaking since these are widely viewed as revolutionary fields. Nanoscience and nanotechnology are considered to have huge potential to bring benefits to many areas of research and application and are attracting rapidly increasing investments from governments and businesses in many parts of the world.

Despite developments in nanoscience and nanotechnology, the Caribbean as a region has not been involved to the extent that more advanced countries have. As such, this symposium aims to provide a stronger focus on the impact and implications of developments in nanoscience/nanotechnology for stakeholders within the Caribbean region, including researchers, academics, university students, government and policy makers, industry partners and the wider public. The symposium will explore various topics under the following themes:

Nanotechnology for Sustainable Energy and Industrial Applications
Nanotechnology for Electronic Device and Sensor Applications
Nanotechnology in Biology, Medicine and Pharmaceuticals
Nanoscale Synthesis, Nanofabrication and Characterization

A July 11, 2014 UWI news release, which originated the news item, provides details about the speakers and more,

An impressive line-up of leading, globally recognised experts from world-class international and regional institutes awaits, including the Public Lecture titled “Science and the Elements of Daily Life,” to be delivered by world-renowned scientist, Professor Anthony K. Cheetham FRS, University of Cambridge, Vice President and Treasurer of The Royal Society. Additionally, the Keynote Address at the Opening Ceremony will be delivered by The Right Honourable Keith Mitchell, Prime Minister of Grenada, with responsibility for Science and Technology in CARICOM.

Speakers at the scientific sessions include Professor Fidel Castro Díaz-Balart (Scientific Advisor to the President of the Republic of Cuba and Vice President of The Academy of Science, Cuba); Professor Frank Gu (University of Waterloo, Canada); Professor Christopher Backhouse (former Director of the Waterloo Institute of Nanotechnology, University of Waterloo, Canada); Professor G. U. Kulkarni (JNCASR, India) and Professor Masami Okamoto (Toyota Technology Institute, Japan).

Students, teachers, academics and the wider public, are all invited and encouraged to attend and use this unique opportunity to engage these leading scientists.

The free Public Lecture is scheduled for Tuesday July 15, 2014, from 5pm-7.30pm, at the Daaga Auditorium, The UWI, St. Augustine Campus. [emphasis mine] The Scientific Sessions take place on Wednesday and Thursday July 16 and 17, 2014, from 8.30am-5pm, at Lecture Theatre A1, UWI Teaching and Learning Complex, Circular Road, St. Augustine. There will also be a small Poster Session to highlight some research done in the areas of Nanoscience and nanotechnology in the Caribbean.

All attendees (to the scientific sessions) must complete and send registration forms to the email address janicejoseph63@hotmail.com by Sunday, July 13, 2014. Registration forms may be downloaded at the Campus Events Calendar entry by visiting www.sta.uwi.edu/news/ecalendar.

A registration fee must be paid in cash at the registration desk on Wednesday July 16, 2014, Day 2, at the start of the scientific sessions.

  • Academic and non-academic:  TT$ 600
  • Graduate student: TT$ 150
  • Undergraduate student: no cost

For further information on the symposium, please visit the Campus Events Calendar at www.sta.uwi.edu/news/ecalendar

I wish them all the best. They seem (judging by the institutions represented) to have attracted a stellar roster of speakers.