Tag Archives: Tuskegee University

Eggshell-based bioplastics

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Adding eggshell nanoparticles to a bioplastic (shown above) increases the strength and flexibility of the material, potentially making it more attractive for use in the packaging industry. Credit: Vijaya Rangari/Tuskegee University

Adding eggshell nanoparticles to a bioplastic (shown above) increases the strength and flexibility of the material, potentially making it more attractive for use in the packaging industry. Credit: Vijaya Rangari/Tuskegee University

A March 15, 2016 news item on Nanowerk describes the research,

Eggshells are both marvels and afterthoughts. Placed on end, they are as strong as the arches supporting ancient Roman aqueducts. Yet they readily crack in the middle, and once that happens, we discard them without a second thought. But now scientists report that adding tiny shards of eggshell to bioplastic could create a first-of-its-kind biodegradable packaging material that bends but does not easily break.

The researchers present their work today [March 15, 2016] at the 251st National Meeting & Exposition of the American Chemical Society (ACS).

A March 15, 2016 ACS news release (also on EurekAlert), which originated the news item, describes the work further,

“We’re breaking eggshells down into their most minute components and then infusing them into a special blend of bioplastics that we have developed,” says Vijaya K. Rangari, Ph.D. “These nano-sized eggshell particles add strength to the material and make them far more flexible than other bioplastics on the market. We believe that these traits — along with its biodegradability in the soil — could make this eggshell bioplastic a very attractive alternative packaging material.”

Worldwide, manufacturers produce about 300 million tons of plastic annually. Almost 99 percent of it is made with crude oil and other fossil fuels. Once it is discarded, petroleum-based plastics can last for centuries without breaking down. If burned, these plastics release carbon dioxide into the atmosphere, which can contribute to global climate change.

As an alternative, some manufacturers are producing bioplastics — a form of plastic derived from cornstarch, sweet potatoes or other renewable plant-based sources — that readily decompose or biodegrade once they are in the ground. However, most of these materials lack the strength and flexibility needed to work well in the packaging industry. And that’s a problem since the vast majority of plastic is used to hold, wrap and encase products. So petroleum-based materials continue to dominate the market, particularly in grocery and other retail stores, where estimates suggest that up to a trillion plastic bags are distributed worldwide every year.

To find a solution, Rangari, graduate student Boniface Tiimob and colleagues at Tuskegee University experimented with various plastic polymers. Eventually, they latched onto a mixture of 70 percent polybutyrate adipate terephthalate (PBAT), a petroleum polymer, and 30 percent polylactic acid (PLA), a polymer derived from cornstarch. PBAT, unlike other oil-based plastic polymers, is designed to begin degrading as soon as three months after it is put into the soil.

This mixture had many of the traits that the researchers were looking for, but they wanted to further enhance the flexibility of the material. So they created nanoparticles made of eggshells. They chose eggshells, in part, because they are porous, lightweight and mainly composed of calcium carbonate, a natural compound that easily decays.

The shells were washed, ground up in polypropylene glycol and then exposed to ultrasonic waves that broke the shell fragments down into nanoparticles more than 350,000 times smaller than the diameter of a human hair. Then, in a laboratory study, they infused a small fraction of these particles, each shaped like a deck of cards, into the 70/30 mixture of PBAT and PLA. The researchers found that this addition made the mixture 700 percent more flexible than other bioplastic blends. They say this pliability could make it ideal for use in retail packaging, grocery bags and food containers — including egg cartons.

In addition to bioplastics, Rangari’s team is investigating using eggshell nanoparticles to enhance wound healing, bone regeneration and drug delivery.

Center for Sustainable Nanotechnology or how not to poison and make the planet uninhabitable

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I received notice of the Center for Sustainable Nanotechnology’s newest deal with the US National Science Foundation in an August 31, 2015 email University of Wisconsin-Madison (UWM) news release,

The Center for Sustainable Nanotechnology, a multi-institutional research center based at the University of Wisconsin-Madison, has inked a new contract with the National Science Foundation (NSF) that will provide nearly $20 million in support over the next five years.

Directed by UW-Madison chemistry Professor Robert Hamers, the center focuses on the molecular mechanisms by which nanoparticles interact with biological systems.

Nanotechnology involves the use of materials at the smallest scale, including the manipulation of individual atoms and molecules. Products that use nanoscale materials range from beer bottles and car wax to solar cells and electric and hybrid car batteries. If you read your books on a Kindle, a semiconducting material manufactured at the nanoscale underpins the high-resolution screen.

While there are already hundreds of products that use nanomaterials in various ways, much remains unknown about how these modern materials and the tiny particles they are composed of interact with the environment and living things.

“The purpose of the center is to explore how we can make sure these nanotechnologies come to fruition with little or no environmental impact,” explains Hamers. “We’re looking at nanoparticles in emerging technologies.”

In addition to UW-Madison, scientists from UW-Milwaukee, the University of Minnesota, the University of Illinois, Northwestern University and the Pacific Northwest National Laboratory have been involved in the center’s first phase of research. Joining the center for the next five-year phase are Tuskegee University, Johns Hopkins University, the University of Iowa, Augsburg College, Georgia Tech and the University of Maryland, Baltimore County.

At UW-Madison, Hamers leads efforts in synthesis and molecular characterization of nanomaterials. soil science Professor Joel Pedersen and chemistry Professor Qiang Cui lead groups exploring the biological and computational aspects of how nanomaterials affect life.

Much remains to be learned about how nanoparticles affect the environment and the multitude of organisms – from bacteria to plants, animals and people – that may be exposed to them.

“Some of the big questions we’re asking are: How is this going to impact bacteria and other organisms in the environment? What do these particles do? How do they interact with organisms?” says Hamers.

For instance, bacteria, the vast majority of which are beneficial or benign organisms, tend to be “sticky” and nanoparticles might cling to the microorganisms and have unintended biological effects.

“There are many different mechanisms by which these particles can do things,” Hamers adds. “The challenge is we don’t know what these nanoparticles do if they’re released into the environment.”

To get at the challenge, Hamers and his UW-Madison colleagues are drilling down to investigate the molecular-level chemical and physical principles that dictate how nanoparticles interact with living things.
Pedersen’s group, for example, is studying the complexities of how nanoparticles interact with cells and, in particular, their surface membranes.

“To enter a cell, a nanoparticle has to interact with a membrane,” notes Pedersen. “The simplest thing that can happen is the particle sticks to the cell. But it might cause toxicity or make a hole in the membrane.”

Pedersen’s group can make model cell membranes in the lab using the same lipids and proteins that are the building blocks of nature’s cells. By exposing the lab-made membranes to nanomaterials now used commercially, Pedersen and his colleagues can see how the membrane-particle interaction unfolds at the molecular level – the scale necessary to begin to understand the biological effects of the particles.

Such studies, Hamers argues, promise a science-based understanding that can help ensure the technology leaves a minimal environmental footprint by identifying issues before they manifest themselves in the manufacturing, use or recycling of products that contain nanotechnology-inspired materials.

To help fulfill that part of the mission, the center has established working relationships with several companies to conduct research on materials in the very early stages of development.

“We’re taking a look-ahead view. We’re trying to get into the technological design cycle,” Hamers says. “The idea is to use scientific understanding to develop a predictive ability to guide technology and guide people who are designing and using these materials.”

What with this initiative and the LCnano Network at Arizona State University (my April 8, 2014 posting; scroll down about 50% of the way), it seems that environmental and health and safety studies of nanomaterials are kicking into a higher gear as commercialization efforts intensify.

A couple comments about science in Japan and China

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A few weeks ago there was a new global research report (written by Jonathan Adams, Christopher King, Nobuko Miyairi, and David Pendlebury) from Thomson Reuters that focused on Japan. From the news release,

This latest report, Global Research Report: Japan, found that:

For the period 2005-2009, physics proved to be Japan’s focus, with roughly 54,800 papers constituting just over 11 percent of the field

The average rate of citation is significantly below those of the other G7 nations. Japan scores 2 percentage points below the world average for the period 2005-2009

Regional collaboration with China and South Korea are likely to be of increasing significance as their domestic research bases grow – another illustration of an emerging Asia/Pacific regional network

This report suggests that Japan is underperforming. From the report,

We now turn to Japan, a G7 economy and the traditional scientific leader of Asia. Japan drove its post-war reconstruction at a phenomenal pace. The post-war baby-boomers, shaped by the nation’s industrious character, provided a committed labor force that enabled strong economic growth into the 1960s and 1970s. However, by the time Japan established its well-founded reputation for excellence based on the quality of its innovative industrial products, the nation was falling into a so-called “Lost Decade” after the economy peaked in the 1980s. This was followed by chronic economic stagnation which continues until today. (p. 3)

There are some opportunities,

The quality of research has improved markedly in some institutions across the Asia-Pacific region and that pattern is likely to become pervasive. The leading institutions will want to partner with established regional centers of excellence. Japan could benefit enormously in gaining access by joining with new partners with new ideas who are just a few hours’ flight away.

Is there a threat here for Japan? The lack of impetus in what has evidently been a very strong research base must be worrying for any policy maker. But regional diversification may be just the stimulus that is needed to rebuild the momentum that enabled Japan to do so well in the post-war period. There is no doubt about the national capacity for rapid and dynamic intellectual and technological advancement. The research challenges of disease, ageing, food security, information technology and social inclusion are all targets to which that capacity could be applied collaboratively with enormous mutual benefit across the region.

I was particularly interested in this report since Japan has been one of the leaders in nanoscience/nanotechnology research. Strangely there’s no mention of either. Here’s the list of main science fields which were included (and which I excerpted) in Table 1 on page 6 of the report,

Physics
Pharmacology & Toxicology
Materials Science
Biology & Biochemistry
Chemistry
Molec. Biology & Genetics
Microbiology
Neuroscience & Behavior
Clinical Medicine
Immunology
Engineering
Space Science
Plant & Animal Science
Geosciences
Agricultural Sciences
Computer Science

I assume research in nanoscience/nanotechnology has been included in several of these classifications. Personally, I think it would be useful to analyse a nanoscience/nanotechnology data subset to find out if it is consistent with or contradicts the conclusions.

You can check out other global reports from Thomson Reuters here. Note: I had to sign up in order to access the reports. It’s free and you do get announcements of newly published reports.

On the China front, there was a June 29, 2010 posting by Dave Bruggeman at Pasco Phronesis about scientific research in China. Dave was responding to an article in the Washington Post by John Pomfret,

Last year, Zhao Bowen was part of a team that cracked the genetic code of the cucumber. These days, he’s probing the genetic basis for human IQ.

Zhao is 17.

Centuries after it led the world in technological prowess — think gunpowder, irrigation and the printed word — China has barged back into the ranks of the great powers in science. With the brashness of a teenager, in some cases literally, China’s scientists and inventors are driving a resurgence in potentially world-changing research.

Unburdened by social and legal constraints common in the West, China’s trailblazing scientists are also pushing the limits of ethics and principle as they create a new — and to many, worrisome — Wild West in the Far East.

First, some of Dave’s response as he unpacks part of this article,

As I suspect this article could get some play in science advocacy and debates over economic competitiveness, I’ve read it a few times, closely. I find it a bit of a puzzle, because it manages to hint at a lot more than it explains. That the headline fails to note the complexity of the issue, which the article tries to express, is no surprise. Where things fall short is in the lack of a consistent theme to the piece and in the continued emphasis on the quantitative in assessing scientific output. [emphases mine]

Since Dave goes on to talk about some of the ethical issues as well I’m going to focus on one of the dominant and damning metaphors used to set this piece.

Conflating cucumbers and IQs is interesting but the kicker (a three word paragraph)  is the 17 year old researcher. We then have China “barging” into research with the “brashness of a teenager” who is “unburdened by social and legal constraints”  and “pushing the limits of ethics and principles” in a “Wild West.”  In case anyone should miss the point, Pomfret’s article ends with this,

“If I had stayed in America, the chances of making a discovery would have been lower,” he said. “Here, people are willing to take risks. They give you money, and essentially you can do whatever you want.” [emphasis mine]

The article carries a somewhat patronizing tone and a blithe disregard for attitudes commonly found in scientists (and others) everywhere not just in China. As for why there are more research checks and balances in what he describes as “The West,” that’s very simple. Researchers crossed ethical lines and public outcry necessitated changes.

For example, there’s the Tuskegee Syphillis Experiment. In the 1920’s a charitable organization approached the US Public Health Service (PHS) about providing medication for men suffering from syphillis in parts of the US South. The project started and then the money ran out so someone decided to change the project. It now became an experiment where doctors could observe the effects of untreated syphillis. No one informed the men. The Tuskegee experiment was continued until the 1970s. From the Tuskegee University website,

While study participants received medical examinations, none were told that they were infected with syphilis. They were either not treated or were treated at a level that was judged to be insufficient to cure the disease.

Over the course of the project, PHS officials not only denied study participants treatment, but prevented other agencies from supplying treatment.

During World War II, about 50 of the study subjects were ordered by their draft boards to undergo treatment for syphilis. The PHS requested that the draft boards exclude study subjects from the requirement for treatment. The draft boards agreed.

In 1943, the PHS began to administer penicillin to patients with syphilis. Study subjects were excluded.

Beginning in 1952, the PHS began utilizing local health departments to track study participants who had left Macon County. Until the end of the study in the 1970s, local health departments worked with the PHS to keep the study subjects from receiving treatment.

The project was finally brought to a stop 1972 when Peter Buxton told the story of the Tuskegee Study to an Associated Press reporter.

Jaw dropping, isn’t it?

To get back to my point, ‘The West’ is not inherently more ethical and while Pomfret does indicate the source for at least some of the funding for this ‘Wild West-type’ (or is it adolescent?) research in China, I’m willing to bet that at least some of it comes from ‘Western’ business interests.

There’s also some implied criticism of the ‘West’ from the Chinese researchers. After all, we’re afraid to “take risks.”

I’d like to see some open and honest discussion (i.e., let’s abandon the imagined moral superiority on anyone’s part) about some of these issues around ethics, competitiveness, and risktaking.