College: City College
Awards: National Science Foundation Graduate Research Fellowship, 2012
Big Ideas at the Nano Level
Nanotechnology is revolutionizing products, from self-cleaning windows to dazzling computer displays, from wrinkle creams to wrinkle-free shirts.
Yet as these products come on the market - some 1,300 in 2008 and far more now - there has been comparatively little attention paid to the potential hazards posed by nanomaterials, which are about the size of proteins and far smaller than the cells in your body.
Discovering how they behave when they're released in the environment (intentionally or not) has broad consequences "not only for us, but for the entire ecosystem," says Charlie Corredor (City College, chemical engineering, 2009), who is in a doctoral program at the University of Washington in Seattle. He is probing the mechanisms of toxicity at the "nano-bio interface" with a 2012 National Science Foundation Graduate Research Fellowship.
"What happens when we discard these small materials into waterways? We're killing our environment, our home," he says. "That's the reason I'm doing environmental nanotoxicity. I'm trying to tell the world how we're affecting what we've got."
It's essential to understand how nanomaterials behave when they come into contact with our bodies, where they can infiltrate - and possibly interfere with or kill cells - he says. "We're able to synthesize, create nanorods and nanoshells for basic commercial applications. They are amazing, and that's the way we're going to go. But we have to be concerned about the fact that they will cause us harm. Preliminary data suggest that nanomaterials can penetrate the membranes of cells. We need to know how to use them and use them as best as possible, so this research is a critical step toward developing safe nanoproducts."
Nanomaterials measure 1 to 100 nanometers, or billionths of a meter; for comparison, a human hair is about 100,000 nanometers in diameter. Nanomaterials can be made from carbon, silicon, gold, cadmium, selenium and other basic elements. They take many forms, with nanowires, nanotubes, quantum dots and fullerenes among them. Each has different properties and potential hazards, depending on factors like size, shape, crystal structure and surface coating.
While some researchers in his lab do computer simulations, Corredor runs experiments to better understand these dynamic systems. For the sake of simplicity, Corredor uses models of biological cell membranes that imitate the natural fluidity and permeability of living cells. With them, he probes the mechanisms and conditions under which engineered nanomaterials can penetrate and disrupt cell membranes.
Working in Professor Jonathan Posner's laboratory, he also is involved with research into nanofluidics (the movement of fluids through microscopic pores), nanofuel cells, self-propelled nanorods that might be used to deliver drugs to target sites, and more.
Corredor was born in Riverside, Calif., but spent most of his youth in Europe and South America with his family, including his Colombian mother.
He graduated from City College having published a remarkable seven research papers. Two, in which he was the primary author, were written with CCNY chemistry Professor John R. Lombardi and Marco Leona of the Department of Scientific Research at the Metropolitan Museum of Art; they recounted research done with the museum and the New York Police Department crime lab that used lasers to quantify and characterize pigments that had been applied in artwork from the 1700s and 1800s.
Lombardi, Corredor says, was extraordinarily supportive and helped him land a grant from CUNY's Louis Stokes Alliance for Minority Participation, an alliance of 17 CUNY colleges and the Graduate Center that supports minority students in the sciences. Stokes' City College project director, Claude Brathwaite, and chemical engineering Associate Professor Ilona Kretzschmar became his academic advisors.
They encouraged him to secure three international Research Experience for Undergraduate grants, supported by the National Science Foundation, at Jilin University in China, the Royal Institute of Technology in Sweden and Pierre and Marie Curie University in Paris. "I was able to see how engineering and chemistry were being used in different parts of the world," he says. "That's a unique opportunity for an undergrad." Along the way, he published two more papers.
"During the time I was in France, I was super-happy, doing science, eating croissants and drinking wine," he says. "When I forgot about grad school, the Stokes program stepped in."
Stokes' National Science Foundation-funded Bridge to Doctorate Program provided him a stipend, graduate courses and laboratory research while he prepared for a PhD. During that year, he researched zinc-air batteries at the CUNY Energy Institute with Distinguished Professor of Chemical Engineering Sanjoy Banerjee and Assistant Professor Daniel Steingart, resulting in another coauthored paper.
He also traveled to graduate schools that interested him, including Arizona State, where he met Posner, "who showed me the passion he had" for research.
So Corredor began his studies at Arizona, and when Posner took an attractive offer to move his operation to the University of Washington, Corredor went with him. Their collaboration has led to two published papers and two more accepted for publication.
"I can't say enough about the support Professor Posner has given me," which includes aid in securing a National Academy Ford Predoctoral Fellowship, as well as the National Science Foundation Graduate Research Fellowship. These are the most prestigious awards that a graduate student in the STEM disciplines (science, technology, engineering and mathematics) can receive. The Ford grant provides an annual $20,000 stipend, plus $2,000 for tuition and fees in each of three years. The NSF grant is for $126,000 over three years of research.
With such good mentorship behind him, Corredor says he looks forward to the day when he, too, becomes a professor and can nurture upcoming talent.
He has an additional ongoing CUNY connection: his fiancée, Keilys Gonzalez, a 2009 CCNY economics BA classmate who is an accountant at the University of Washington. "We have a CCNY bumper sticker on the back of our car and sweatshirts from CUNY," he says. "I'm proud to be a CUNY alumnus; it was a fantastic experience."