Student Researchers Go for Gold

September 15, 2008

Scientists take different paths in their chosen fields. Robert Tanguay describes his in an online interview by Sandra Uesugi of OSU's Environmental Health Sciences Center.

Members of Tanguay's research team have their own stories to tell. They come from Salem, Seattle and a small town in the Colorado Rockies. One is a major in the U.S. Air Force Reserve. Another studied wildlife ecology in American Samoa. Some collaborate with scientists at other Oregon universities through the Oregon Nanoscience and Microtechnologies Institute (ONAMI). Here are their paths to nanoscience.

Lisa Truong

Ph.D. student
Department of Environmental and Molecular Toxicology

TruongNanomaterials are on the health-care horizon. Gold-based materials have long been used to reduce inflammation associated with rheumatoid arthritis and to improve biomedical imaging. They have intrigued Lisa Truong since she first heard about their potential to help solve intractable problems from cancer to heart disease.

Truong, who grew up in the Seattle area, wants to know how gold nanomaterials behave in the body. Through ONAMI's Safer Nanomaterials and Nanomanufacturing Initiative, she is testing products from Professor Jim Hutchison's University of Oregon lab, which has created "green" methods (highly efficient, precise and less toxic) for making gold nanomaterials.

"We actually know how they're made every step of the way," says Truong. Such information about manufacturing methods, chemical composition and purity is crucial for linking nanomaterial characteristics to the outcomes of tests in the OSU zebrafish lab.

Moreover, ONAMI provides Truong with direct access to information. "I can pick up the phone and ask questions about a nanomaterial I'm working with. I can ask how many ligands (a molecule that bonds with a metal) is on the surface of a nanomaterial, rather than have to look it up or wait online," she says.

Truong's desire for better health care is personal. As a child, she watched her grandparents struggle with heart problems. Diagnostic tests and treatments made them sick. "I didn't want to be a doctor," she says. "But I wanted to develop the technology that would help them."

Kate Saili

Ph.D. student
Department of Environmental and Molecular Toxicology

SailiKate Saili makes movies. Her films won't show in theaters any time soon, but they do show one of the dramatic features of zebrafish - their ability to regenerate tissues that have been injured (see Saili's microscope video of a regenerating zebrafish tailfin).

Saili, who grew up in Kalispell, Montana, studies the effect of nanomaterials on inflammation. She uses transgenic zebrafish whose white blood cells fluoresce under ultraviolet light. White blood cells are foot soldiers in the inflammation process, and in her experiments, Saili observes that process as it proceeds in the presence of nanomaterials.

First, Saili immerses a zebrafish in an anesthetic. Then she removes the tip of the tailfin. As the fish's immune system kicks in, Saili places the animal in a solution containing nanomaterials that have been designed by a scientist at Tennessee State University potentially to treat inflammation. Through a microscope, she captures images of the white blood cells rushing to the injured fin.

"I'm really interested in how the immune system works," says Saili, who has a bachelor's degree in biology from Carroll College in Helena, Montana. Her studies show that fewer white blood cells migrate to the site of the injured fin when certain gold- or silver-based nanomaterials are present. "All we can say for sure is that nanoparticles are reducing the number of white bloods cells that migrate to or remain at the site of an injury. We don't know why," she adds.

Before coming to OSU, Saili was studying wildlife in American Samoa. Someday, she would like to monitor wildlife health and apply what she learns to human health. "I think you can get a lot farther and do lot more interesting and relevant work with a molecular foundation. What I want to do is investigate a disease, look at the mechanics behind it. I came to OSU," she says, "because I knew it has a good toxicology program."

Joe Fisher

Ph.D. student
Department of Public Health

FisherAs the nanotechnology industry grows, Joe Fisher wants to make sure that public health problems don't grow with it. "I know that this industry is going to develop in a big way," he says. "My focus is preventative health and safety. I don't want people to be unduly exposed to potentially dangerous substances."

To his quest for nano safety, Fisher brings two OSU engineering degrees (a bachelor's in agricultural and a master's in industrial engineering) and a second bachelor's from Cal State-Monterey in applied computing. He has more than 10 years of experience as an industrial engineer and information technologist with Ernst & Young, Oracle and the Department of Defense. As a major and medical officer in the U.S. Air Force Reserve, he specializes in occupational health, including industrial hygiene and radiation safety.

Fisher, who grew up in Monterey, has yet to decide on the approach he'll take in his research. Working with Robert Tanguay and Daniel Sudakin in Environmental and Molecular Toxicology and with Anna Harding in Public Health, he expects to focus on links between nanomaterial exposure and human health.

"There are plenty of people being unduly exposed because they don't have the knowledge to be aware of the hazards." He says. "I can see the engineering technology end of it really taking off. I'd love to do that, but I'm not going to build stuff. I have something else to offer, and that's public health."

Fisher sees Oregon as the right place for him. "Oregon has always been a hotbed for semiconductors," he says, "and now it is for nano."

Olga Bistrika

First-year undergraduate
Department of Biochemistry and Biophysics

Last summer, Olga Bistrika got an early jump on her college career. At the same time, her research advanced knowledge about the effects of nanomaterials on the environment.

As a participant in the Saturday Academy program at Portland State University, the graduate of North Salem High School worked in OSU scientist Stacey Harper's lab. She focused on zinc oxide, a nanomaterial found in sunscreens and other cosmetics.

Her challenge was to consider how exposure to zinc oxide affects the ability of aquatic organisms to feed. A common freshwater insect, known as daphnia or "water flea," was her model of choice.

In her experiments, Bistrika placed daphnia into solutions with concentrations of zinc oxide nanomaterials ranging between 1 and 100,000 parts per billion. She then added a chemical that, if ingested by the daphnia, would make them glow. By recording how many daphnia glowed in each solution, she could see how many were ingesting the chemical.

She found that daphnia exposed to higher concentrations of zinc oxide ingested less of the chemical. That suggests that the nanomaterial was interfering with the daphnia's feeding process.

"Scientists are trying to make the materials we use to test and the products themselves safer and better for the environment," Bistrika says. As a self-professed environmentalist, she likes contributing knowledge that can lead to safer products.

While her research is focused on earthly things, Bistrika's dream is to work for NASA. "I've always been into science," she adds, "and it would be awesome to study materials from other planets."

Stacey Harper

Post-doctoral scientist
Department of Environmental and Molecular Toxicology

HarperDuring a two-year post-doctoral stint with the U.S. Environmental Protection Agency (EPA) in Las Vegas, Nevada, Stacey Harper learned that she was not meant to live in a desert. So the native of Silt, Colorado (population 1,740), jumped at a chance to move to western Oregon and work with a promising model system for evaluating health risks.

Nanotoxicology was just emerging as a priority in risk assessment when she left the EPA in 2005. Robert Tanguay had developed OSU's zebrafish lab into a system for scanning materials rapidly for potential health risks. Harper and her team of graduate and undergraduate students have now screened more than 150 types of nanomaterials and created a method for ranking toxicity.

Key to Harper's work has been her collaboration with ONAMI. "ONAMI has helped me a lot personally to advance in the nanotoxicology field," she says. "The industry partners that I collaborate with are very willing for us to use their materials because they are as concerned with potential toxicity as we are. And they want to know ahead of time if this (a specific nanomaterial) is something worth pursuing."

Nanomaterial risk analysis is very much in its infancy, Harper adds. Scientists are still learning how nanomaterials interact with cells and how to compare impacts on development in zebrafish, mice, cell cultures and other model systems.

Nevertheless, she is optimistic about this growing industry. "It's an opportunity to start designing chemicals and pesticides and drugs that are very targeted, very specific and less toxic, less hazardous," Harper says. "It's an opportunity for sustainability in a rapidly emerging industry, and that is extremely exciting."