Category: Chemistry Page 5 of 7

Middle Schoolers Get a BOOST in Chemistry

On July 2, 2015

In Chemistry, Guest Post, Science Communication & Education

Seventy middle school students oohed and aahed as soap bubbles full of propane burst into flame.

“First row, don’t get burned!” shouted Douglass Coleman, director of the BOOST program, a summer science camp program for students in grades 5 through 12.

Duke Chemistry Outreach student Danielle Holdner makes fire do tricks.

Duke chemistry instructor Ken Lyle and student Danielle Holdner brought their travelling chemistry demos to the MDB Trent Semans Center Monday for the BOOST kids.

They created chemical smoothies and rainbows that taught the students about acids and bases. They sparked up fireworks to teach the students about gases such as butane and propane.

BOOST (Building Opportunities and Overtures in Science and Technology) is designed to teach kids from all cultures and racial backgrounds about science and inspire them to pursue careers in science, technology engineering, medicine and related fields.

“My favorite experiment was the bubbles filled with propane,” said Karen Gonzazlez a student in the program. “I enjoyed seeing them blow up with fire.”

BOOST director Coleman, who is known for his playful antics at the presentations, said the program opens doors for students and provides them with opportunities.

“These kids would not be able to meet with professors or work in labs if it was not for this program,” said Coleman. “It is important that they are around students just like them who are striving and building for success.”

BOOST is divided into three groups depending on grade level and interest of science. Rising 5th and 6th graders are in Boost, rising 7th graders who are interested in food science/chemistry or technology are in Boost XL. Rising 8th graders interested in biological science or engineering are in Boost XXL.

[vimeo 55126467 w=500 h=281]

Teachers and junior coaches at the program said it keeps students eager to learn science.

“This program keeps students engaged and motivated in hands- on activities, “said Stefanie Joyner, a teacher for Boost XXL.

Sierra Foster, junior coach for Boost XXL, said BOOST can open students’ eyes to new science.

“This program can build their knowledge and help them understand more than what they might already know,“ said Foster.

BOOST is funded through a grant from the Science Education Partnership Award (SEPA) from the National Institute of Health (NH).

For more information on BOOST, visit http://sites.duke.edu/boost/ or call (919) 681-1045.

Guest Post by Shakira Warren, NC Central University summer intern

Outsmarting HIV With Vaccine Antigens Made to Order

By Robin Smith

On June 29, 2015

In Biology, Chemistry, Computers/Technology, Global Health, Medicine

AIDS vaccine researchers may be one step closer to outwitting HIV, thanks to designer antibodies and antigens made to order at Duke.

HIV was identified as the cause of AIDS in 1983. Despite decades of progress in understanding the virus, an effective vaccine remains elusive.

The lack of success is partly due to HIV’s uncanny ability to evade the immune system.

Duke graduate student Mark Hallen and his advisor, Duke computer science and chemistry professor Bruce Donald. Hallen was awarded a 2015 Liebmann Fellowship for graduate studies.

Now, a team of researchers including Duke computer scientist Bruce Donald and graduate student Mark Hallen have published a 3-D close-up of a designer protein that, if injected into patients, could help the immune system make better antibodies against the virus — a step forward in the 30-year HIV vaccine race.

Led by structural biologist Peter Kwong at the Vaccine Research Center in Bethesda, Maryland, the team’s findings appeared online June 22 in the journal Nature Structural & Molecular Biology.

More than 35 million people worldwide are living with HIV, and about two million more people are infected each year.

Antiretroviral drugs can prevent the virus from reproducing in the body once someone is infected, but only a vaccine can stop it from spreading from one person to the next.

Vaccines work by triggering the immune system to make specialized proteins called antibodies, which prime the body to fight foreign substances. But in the case of HIV, not all antibodies work equally well.

One reason is that HIV is always mutating in the body.

3D print of HIV. Thousands of times smaller than the width of a human hair, the virus is covered with proteins (purple) that enable it to enter and infect human cells. Photo by Daniel Mietchen via Wikimedia Commons.

3D print of HIV. In real life the virus is thousands of times smaller than the width of a human hair. HIV is covered with proteins (purple) that enable it to enter and infect human cells. Photo by Daniel Mietchen via Wikimedia Commons.

HIV incorporates its genetic material into the DNA of its host, hijacking the cell’s replication machinery and forcing it to make more copies of the virus. Each round of replication generates small genetic “mistakes,” resulting in slightly different copies that the host’s antibodies may no longer recognize.

Even before the body makes an antibody that works against one strain, the virus mutates again and makes a new one.

“It’s a race against a moving target,” said Hallen, who was also an undergraduate at Duke majoring in chemistry and mathematics.

In the early 1990s, researchers discovered that a tiny fraction of people infected with HIV are able to produce antibodies that protect against many different strains at once.

These “broadly neutralizing antibodies” fasten to the virus’s surface like a key in a lock and prevent it from invading other cells.

But HIV can evade detection by these powerful antibodies, as the part of its outer coat that is vulnerable to their attack is constantly changing shape.

To overcome this problem, first the researchers needed a close-up look at the region of interest — a spike-shaped virus protein known as Env — in its most vulnerable state.

A 3-D closeup of a key virus protein frozen in a shape the researchers say could serve as a template for a vaccine. Image courtesy of Bruce Donald.

With this 3-D blueprint in hand, Hallen and former Duke PhD Ivelin Georgiev developed a scoring system and rated dozens of antibodies according to how well they bound to it. They confirmed that the specific conformation of the Env protein they identified was visible to effective antibodies but not ineffective ones.

The team then identified amino acid sequence changes that would freeze the protein in the desired shape.

Once locked in place, the researchers say, the protein could be injected into patients and used to coax their immune systems into preferentially churning out only the most effective antibodies.

“The idea is to ‘tie’ the protein so that it can’t transition to some other conformation and elicit ineffective antibodies as soon as the effective antibodies bind,” Donald said.

Support for this research included grants from the US National Institutes of Health, the US National Institutes of General Medical Sciences, the US National Institute of Heart, Lung and Blood, the US National Science Foundation and the Bill and Melinda Gates Foundation.

CITATION: “Crystal Structure, Conformational Fixation and Entry-Related Interactions of Mature Ligand-Free HIV-1 Env’,” Kwon, Y. et al. Nature Structural & Molecular Biology, June 22, 2015. DOI: 10.1038/nsmb.3051.

Robin Smith joined the Office of News and Communications in 2014 after more than ten years as a researcher and writing teacher at Duke. She covers the life and physical sciences across campus.

Origami-Inspired Chemistry Textbook Brings Molecules To Life

By Anika Radiya-Dixit

On February 13, 2015

In Biology, Chemistry, Computers/Technology, Engineering, Mathematics, Science Communication & Education

by Anika Radiya-Dixit

Your college textbook pages probably look something like the picture below – traffic jams of black boats on a prosaic white sea.

Textbook without illustrations.

But instead of reading purely from static texts, what if your chemistry class had 3D touch-screens that allowed you to manipulate the colors and positions of atoms to give you visual sense of how crystal and organic structures align with respect to each other? Or what if you could fold pieces of paper into different shapes to represent various combinations of protein structures? This is the future of science: visualization.

Duke students and staff gathered in the Levine Science Research Center last week to learn more about visualizing chemical compounds while munching on their chili and salad. Robert Hanson, Professor in the Department of Chemistry at St. Olaf College, was enthusiastic to present his research on new ways to visualize and understand experimental data.

Exhibition poster of “Body Worlds”

Hanson opened his talk with various applications of visualization in research. He expressed a huge respect for medical visualization and the people who are able to illustrate medical procedures, because “these artists are drawing what no one can see.” Take “Body Worlds,” for example, he said. One of the most renowned exhibitions displaying the artistic beauty of the human body, it elicited a myriad of reactions from the audience members, from mildly nauseated to animatedly pumped.

Hanson also spoke about the significance of having an effective visualization design. Very simple changes in visualization, such as a table of numbers versus a labeled graph, can make a “big difference in terms of ease of the audience catching on to what the data means.” For example, consider the excerpt of a textbook by J. Willard Gibbs below. One of the earliest chemists to study the relationship between pressure and temperature, Gibbs wrote “incredibly legible, detailed, verbatim notes,” Hanson said. Then he asked the audience: Honestly, would one read the text fervently, and if so, how easy would it be to understand these relationships?

Excerpt of J. Gibbs’ text.

Not very, according to James C. Maxwell, a distinguished mathematician and physicist, who attempted to design a simpler mechanism with his inverted 3D plaster model.

Maxwell’s plaster model of Gibbs’ surface

Subsequent scientists created the graph shown below to represent the relationships. Compared to the text, the diagram gives several different pieces of information about entropy and temperature and pressure that allow the reader to “simply observe and trace the graph to find various points of equilibrium that they couldn’t immediately understand” from a block of black and white text.

Graphical view of Gibbs’ theory on the relation between temperature and pressure.

Hanson went further in his passion to bring chemistry to the physical realm in his book titled “Molecular Origami.” The reader photocopies or tears out a page from the book, and then folds up the piece of paper according to dotted guidelines in order to form origami molecular “ornaments.” The structures are marked with important pieces of information that allow students to observe and appreciate the symmetry and shapes of the various parts of the molecule.

3D origami model of marcasite (scale: 200 million : 1)

One of his best moments with his work, Hanson recounted, was when he received a telephone call from some students in a high school asking him for directions on how to put together a 3D model of bone. After two hours of guiding the students, he asked the students what the model finally looked like – since he had knowledge of only the chemical components – and was amused to hear a cheeky “He doesn’t know.” Later that year, Hanson was rewarded to see the beautiful physical model displayed in a museum, and was overjoyed when he learned that his book was the inspiration for the students’ project.

More recently, Hanson has worked on developing virtual software to view compounds in 3D complete with perspective scrolling. One of his computer visualizations is located in the “Take a Nanooze Break” exhibition in Disneyland, and allows the user to manipulate the color and location of atoms to explore various possible compounds.

“Touch-A-Molecule” is located in the Epcot Center in Disneyland.

By creating images and interactive software for chemical compounds, Hanson believes that good visualization can empower educators to gain new insights and make new discoveries at the atomic level. By experimenting with new techniques for dynamic imagery, Hanson pushes not only the “boundaries of visualization,” but more importantly, the “boundaries of science” itself.

Professor Hanson explains how to visualize points of interaction on a molecule.

Contact Professor Hanson at hansonr@stolaf.edu.

Read more about the event details here.

View Hanson’s book on “Molecular Origami” or buy a copy from Amazon.

Ben Wang: Food lover and undergraduate researcher

By sa160@duke.edu

On January 29, 2015

In Biology, Chemistry, Medicine, Students

Ben Wang in rural Appalachia Credit: Ben Wang

By Nonie Arora

Ben Wang, a senior Evolutionary Anthropology major from New Jersey, strongly believes we are what we eat. A foodie, scientist, and future health care practitioner, he thinks that changing food habits can improve our nation’s health.

“When we came to Duke, our summer reading book was Eating Animals,” he said. “I felt so many emotions while I was reading the book. It really impacted the way I think about food. In fact, I became a pescetarian (a fish-eating vegetarian).”

Freshman year, Wang knew he had this interest in food, but he didn’t know how to incorporate it into his academic world.

During his second year, Wang started to find his way. “I remembered the topic when I was hunting for a research lab, and started working in Dr. Tso-Pang Yao’s metabolism lab so that I could learn more about how nutrition directly impacts health,” he said.

Wang spent time investigating proteins that increase or decrease the amount of “mitochondrial fusion” that happens in cells. Wang explained that metabolism is how our bodies process food and distribute nutrients, and these compounds help in that process.

“I really enjoyed this lab because the topic was directly related to patient care and our research had direct pharmacologic applications,” Wang said.

Farm Fresh tomatoes! Credit: Ben Wang

In the summer of 2014, he pursued a Bass Connections fellowship in rural Appalachia, in one of the most impoverished counties in the US.

He participated in a Farm-to-Table partnership between local Appalachian farms and a middle school. This partnership was part of a broader program for Appalachian girls. He coordinated the logistics and ended up doing much of the culinary work for the partnership, cooking up delicacies with ingredients like swiss chard, beets, and kale.

“I really wanted to go all the way in introducing a fresh perspective to these women,” Wang said, “I had to convince the girls that these veggies would taste good.”

Farm to Table initiative in action. Credit: Ben Wang

They did not always like his creations.
He says one student told him, “I’m not going to eat this hippie food.”

But he persevered, and ultimately most of the girls were excited about what they had learned and reevaluated the way they ate.

Maintaining lasting gains will be difficult because much of the food would have been unaffordable to the girls on their own. In the town that they live in, the closest supermarket is a Walmart a half hour away. Other than that, there is a Dollar General and Hillbilly Market, neither of which stock fresh produce, according to Wang.

However, Wang thinks that showing these girls there are food options beyond those that they have experienced was valuable, and that they can choose to strive for them if they want to.

Changing eating habits, one delicious meal at a time. Credit: Ben Wang

As for Wang, he is headed to dental school in the fall and hopes to include nutritional awareness in his future practice to help his patients achieve better systemic health.

A Made-to-Order Materials Menu

By Karl Bates

On November 11, 2014

In Chemistry, Computers/Technology, Engineering, Guest Post

Guest Post by Ken Kingery, Pratt School of Engineering

If you think ordering a drink from Starbucks can be a tall order, try picking out the right material for a new product or experiment. An iced, half-caff, four-pump, sugar-free, venti cinnamon dolce soy skinny latte may be a mouthful, but there are hundreds of thousands of known—and unknown—compounds to choose from, each with their own set of characteristics.

Screenshot of the AFLOW library search interface. The software combs through four giant databases of chemical compounds.

For example, take the family of materials Bi2Sr2Can-1CunO2n+4+x, or bismuth strontium calcium copper oxide for short, if you can call it that. These compounds have the potential to change the world because of their ability to become superconducting at relatively high temperatures. But each sibling, cousin or distant relative has its own physical variations…so how to choose which to pursue?

Thanks to Stefano Curtarolo and his research group, now there’s an app for that.
Curtarolo leads a collection of research groups from seven universities specializing in something they call materials genomics. The group—called the AFLOW consortium—uses supercomputers to comb databases for similar structures and builds theoretical models atom-by-atom to predict how they might behave.

With help from several members of the consortium, Pratt School of Engineering postdocs Cormac Toher, Jose Javier Plata Ramos and Frisco Rose, along with Duke student Harvey Shi, have spent the past few months building a system that combs through four materials databases. Users can choose the elements and characteristics they want a material to have—or not to have—and the website will play matchmaker.

Want a two-element compound containing either silicon or germanium—but not gallium—that is stable enough to withstand high temperatures? Not a problem. How about an electric insulator made from transition metals with a certain crystal structure? AFLOW has you covered.

Stefano Curtarolo is a professor of mechanical engineering and materials science at Duke

One of the four databases searched by the program draws from an international collection of compounds with structures known from experimentation. The other three contain single- double- or triple-element compounds, and are not limited to previously explored materials. Through their molecule-building algorithms, the AFLOW consortium is constantly adding prospective materials to these four libraries.

The search engine currently can sort through more than 622,000 known and unknown compounds, and more than 1,000 new ones are added each week. Curtarolo, a professor of materials science and physics, hopes that the open-source program will continue to grow in materials and searchable characteristics to help scientists connect to their ideal material. To see how it works for yourself, take it for a test drive here.

As for an equivalent database of coffee drinks, that has yet to be built. So if you’re looking through AFLOW for a hot, lactose-free drink featuring 150 to 200 mg of caffeine and less than 200 calories made with beans from South America, you’re out of luck.

A Quiet but Fundamental Case in the Flame Retardant Debate

By Olivia Zhu

On September 4, 2014

In Cancer, Chemistry, Environment/Sustainability

By Olivia Zhu

The dangers of flame retardants have long been the source of public health debate, thrust into the public eye by legislators, non-profit organizations, and special interest groups.

Often missing, though, is the story of the extensive scientific background necessary to ground these arguments: Heather Stapleton, the Dan and Bunny Gabel Associate Professor of Environmental Ethics and Sustainable Environmental Management, and research scientist Ellen Cooper and their teams fill this role at the Nicholas School of the Environment.

As a former intern at the Center for Environmental Health, where I advocated against legislation that promotes the use of flame retardant chemicals, I was fascinated to learn the technical side of the conversation from Cooper.

Flame retardants have been present in furniture and other foam-based items largely due to fire safety regulations like California’s TB117, which requires home furniture to resist bursting into flame for a certain amount of time. Historically, manufacturers have met this standard by using flame retardant chemicals that may impact brain development in children or even cause cancer. Consequently, foam producers have added flame retardants to all their foam, even foam meant for products not covered under TB117. Evidently, the resulting flame retardant-laden selection of furniture poses a threat to the health of consumers, who effectively have little choice in protecting themselves against potentially dangerous chemicals.

Nicholas school environmental chemist Heather Stapleton in the lab. (Duke Photography)

Unsurprisingly, scientifically studying flame retardants requires rigorous chemical analysis. Ellen Cooper, along with the Analytical Chemistry Core, specializes in preparing foam samples and running them through mass spectrometers to identify the flame retardants. The Chemistry Core collaborates with the Stapleton Lab to ensure accurate analysis of often-fragile flame retardants. Both are a part of Duke’s Superfund Research Center.

Cooper’s work has been instrumental in the Stapleton lab’s creation of a foam testing service for consumers. In January, the Stapleton lab started the first foam testing service ever open to the public! Now, consumers can send in up to five samples from their furniture to receive complimentary results which are provided by the Analytical Chemistry Core. On the foam testing website, consumers can also find statistics on common sources of flame retardants and information on how to avoid exposure to flame retardants. Through these efforts, the Stapleton lab is allowing consumers to take back their autonomy.

Additionally, Cooper is working to create a database of all collected samples. Currently, there exists no definite data on which manufacturers’ products contain which flame retardants, or how levels of flame retardants in furniture have changed over time. With enough data points, Cooper and her team hope to create such heat maps or time analyses, making for a more informed debate, and ultimately a more well-protected public.

Duke Researchers Cited for Their Influence

By Karl Bates

On June 13, 2014

In Behavior/Psychology, Business/Economics, Cardiology, Chemistry, Environment/Sustainability, Faculty, Global Health, Mathematics, Medicine, Physics

We are the champions, my friend.

By Karl Leif Bates

A new compilation of the world’s most-cited scientists just released by Thomson Reuters (our friends from March Madness), shows that 32 Duke researchers are in the top one percent of their fields.

There are 3215 most-cited scientists on the list, so perhaps that makes Duke the one percent of the one percent?

Most-cited means a particular paper has been named frequently in the references by other papers in that field.

And that “is a measure of gross influence that often correlates well with community perceptions of research leaders within a field,” Thomson Reuters says. The database company admits their study methodology does favor senior authors who have had their papers out there longer, but there are quite a few younger Duke researchers in this list too.

From the Medical Center, the tops in citations in clinical medicine are cardiologists Eric Peterson, Robert Califf, Christopher Granger, and Eric Magnus Ohman. Michael Pencina, a biostatistician at the Duke Clinical Research Institute, is also most-cited in clinical medicine.

Perhaps not surprisingly, Nobel laureate, biochemist, and father of the G-protein coupled receptor Robert Lefkowitz made the list in pharmacology and toxicology.

Barton Haynes and David Montefiori of the Duke Human Vaccine Institute are listed in the microbiology category.

Medical School basic scientist Bryan Cullen of Molecular Genetics and Microbiology was cited in microbiology.

In psychiatry/psychology, A. John Rush, the vice dean for clinical research at Duke-NUS School of Medicine in Singapore, made the list, as did Richard Keefe, Joseph McEvoy of psychiatry and Avshalom Caspi, and Terrie Moffitt of Psychology & Neuroscience in Arts & Sciences.

Also from Trinity College of Arts and Sciences, Ahmad Hariri and HonaLee Harrington of Psychology & Neuroscience also made the list in psychiatry/psychology. Benjamin Wiley was oft-cited in Chemistry, James Berger and Ingrid Daubechies in mathematics, and plant biologists Philip Benfey, Xinnian Dong and Tai-Ping Sun in the category of plant and animal science.

Sanford School of Public Policy Dean Kelly Brownell is on the list in general social sciences, along with Arts & Sciences sociologist James Moody and nutrition researcher Mary Story of community and family medicine and the Duke Global Health Institute.

Nicholas School of the Environment researchers Robert Jackson and Heather Stapleton were cited the environment/ecology category.

From the Pratt School of Engineering, David R. Smith was cited in the physics category and Jennifer West in materials science.

The economics and business category includes Dan Ariely along with his Fuqua School of Business colleagues Campbell Harvey and Arts & Sciences economist Tim Bollerslev.

The Thomson Reuters analysis is based on their Web of Science database. This is the first time it has been done since 2001, when there were 45 Duke names on the list (including five that appeared again this time), but the methodology has changed somewhat.

UPDATE – There’s now a full PDF report from Thomson Reuters for download – http://sciencewatch.com/sites/sw/files/sw-article/media/worlds-most-influential-scientific-minds-2014.pdf

Copper Nanowires Now Match Performance of Leading Competitor

By Erin Weeks

On March 24, 2014

In Chemistry, Computers/Technology, Faculty, Nanotech, News Release

Images of the first and last stages (intermediate photo excluded) of the copper nanowire growth as seen through a transmission electron microscope. Interestingly, though not visible here, the nanowires are pink. (Photo: Shengrong Ye)

Images of the first and last stages of the copper nanowire growth as seen through a transmission electron microscope. Interestingly, though not visible here, the nanowires are pink. (Photo: Shengrong Ye)

By Erin Weeks

Copper nanowires are one step closer to becoming a low-cost substitute for the transparent conductor in solar cells, organic LEDs and flexible, electronic touch screens. A team at Duke has succeeded in making transparent conductors from copper nanowires that are only 1% less transparent than the conventional material, indium-tin oxide (ITO).

Copper is 1000 times more abundant and 100 times cheaper than indium, the main ingredient in ITO, but for years copper nanowires have lagged behind in terms of transmittance.

Assistant chemistry professor Benjamin Wiley’s lab has fixed that — simply by changing the aspect ratio, or the proportion of length to diameter, of the nanowires. The findings were reported recently in the journal Chemical Communications.

“We finally have something competitive with ITO in terms of performance, and we got there by increasing the nanowire aspect ratio,” Wiley said.

Using a special growth solution, Wiley’s lab can “sprout” the nanowires in under half an hour and at normal atmospheric pressure. Further tweaking the synthesis, the team was able to prompt the nanowires to grow long and uniform in diameter, instead of tapered and baseball bat-shaped, which have lower aspect ratios.

The paper also includes the images of copper nanowire growth as observed in real time, the first time such observations have been published.

Still, at least one kink remains before the nanowire technology will be attractive for commercial production. The copper nanowires are susceptible to corrosive oxidation, which Wiley’s team has tried to remedy by coating the nanowires with materials like nickel. Unfortunately, a nickel coating reduces the transparency of the nanowire films.

“So now we’re trying to figure out ways to protect the nanowires without decreasing the performance,” Wiley said. “We’re focused on getting the same performance, but having more stability.”

Citation: “A rapid synthesis of high aspect ratio copper nanowires for high-performance transparent conducting films.” Shengrong Ye, Aaron Rathmell, et al. Chemical Communications, March 11, 2014. DOI:10.1039/c3cc48561g.

New Course Offers Lessons from Lasering Priceless Art

By Erin Weeks

On January 20, 2014

In Chemistry, Computers/Technology, Faculty, News Release, Students, Visualization

Duke graduate student Tana Villafana and chief conservator at the NC Museum of Art William Brown stand over The Crucifixion (inset). (Photo: Martin Fischer)

By Erin Weeks

A group of chemists at Duke University has gained recognition in recent years for shooting lasers at medieval artwork — technology that allows a harmless peek at the many layers and materials in a painting and offers insight into long gone eras and artists. Now, Duke students will have the chance to learn from this pioneering work at the intersection of chemistry and art history in a new course on the science of color.

The course coincides with the publication of the first scientific measurements from the laser work, reported Jan. 20 in the Proceedings of the National Academy of Sciences.

“The images we have now are enormously better than a year ago,” said Warren S. Warren, head of the lab performing the imaging and the James B. Duke professor of chemistry. He and fellow Duke authors, grad student Tana Villafana and associate research professor Martin Fischer, have not only demonstrated the technology works — they’ve shown it works at an incredible level of detail, telling the difference, for example, between nearly identical pigments.

But lasering The Crucifixion by Puccio Cappano was just the start, as the team envisions countless more cultural applications of the technology. Given enough funding and manpower, they could visualize ancient scrolls of text too fragile to unroll, reveal the bright colors that once adorned Greek statues, learn the secrets of China’s terracotta warriors, and even detect the beginnings of pigment degradation in aging artwork.

There are talented people in art conservation, Warren said, whose work could benefit from more advanced technology, and there are talented people at the cutting-edge of laser science looking for meaningful ways to apply their inventions. For the past several years, Warren’s lab has brought these people together.

Now, he hopes to accomplish something similar with students at Duke. Warren, Fischer, and another chemistry instructor, Adele DeCruz, are teaming up to teach “The Molecular, Physical, and Artistic Bases of Color” in the second half of spring semester.

The class will visit the Nasher Museum of Art, the North Carolina Museum of Art in Raleigh, and possibly even the National Gallery of Art in Washington, D.C, to learn first-hand from art conservators and working artists. Students can expect to learn about how humans have used and made pigments over the millennia; how color works at a molecular level; and the basics of how human vision, microscopes, cameras, and lasers all see or image color.

Students can register for the half course, CHM 590, until the add/drop deadline for classes on January 22. “Students should not be scared off by the course number,” Warren said. “The prerequisite is one college-level science course, and the intent is to make both the science and artistic components accessible to a broad audience.”

Funding for the research was provided by National Science Foundation grant CHE-1309017.

CITATION: “Femtosecond pump-probe microscopy generates virtual cross-sections in historic artwork.” Tana E. Villafana, William P. Brown, et al. Proceedings of the National Academy of Sciences, Jan. 20, 2014. Doi: 10.1071/pnas.1317230111

Keely Glass, the Omni-Chemist

By Karl Bates

On January 13, 2014

In Cancer, Chemistry, Guest Post, Physics, Students

Guest post by Addie Jackson, North Carolina School of Science and Mathematics

Keely’s picture from Linked-In

Ask Keely Glass how she would describe her research to a third grader, and she laughs while thinking of the best way to explain.

“So, say you’re sitting next to your friends. One has really black hair and one has red hair. They have different hair colors, because their hair colors come from the different pigments. Your friend with black hair has more eumelanin, while your friend with red hair has pheomelanin.”

A PhD candidate in the chemistry department at Duke, Glass currently does research on analytical methods to analyze these pigments in biological and historical samples. She’s also using those skills to provide direct chemical evidence for the presence and preservation of eumelanin in the fossil record.

Trust us, that’s a fossil squid. (Courtesy of Willsquish on Wikimedia Commons.)

Glass elaborates by describing a common fascination with squids, also known as cephalopods, who release pure black eumelanin when faced with a predator. Two kinds of melanin are present in nature: eumelanin (brown to black in color) and pheomelanin (yellow to red). Through her work, she and her team have verified that eumelanin is preserved in the fossil record, and showed that it can be identified directly using its known chemical signature. They have also found that the eumelanin identified in the fossil record is not significantly different from the modern eumelanin, meaning it hasn’t evolved in the more than 160 million years since.

Another lab at Duke, run by Professor Warren S. Warren, uses a pump-probe microscopy system to characterize melanins to attempt to find statistically significant variations between melanomas (skin cancers) that do not develop metastases. The hope for this project is to improve diagnostic accuracy for these metastatic melanomas, through analyzing the melanin distribution in “old” archived (stored for >10 years) tissue samples. Glass says, “The paper I wrote with them essentially says if melanin resists degradation (stays intact and doesn’t alter) over more than 160 million years, it’s fairly clear that it will resist degradation in storage for 10 years. In other words, it’s pretty clear that these archived tissue samples are still viable for melanin analysis.”

Fourteen months in the life of one man’s nodular melanoma. (Courtesy of 0x6adb015 via Wikimedia Commons.)

Working with the Warren group, Glass also found that the pump-probe system was sensitive to the higher iron-concentration fossilized squid melanin as compared with modern cephalopod melanin. They were able to mirror the iron-independent signal by adding iron to modern cephalopod melanin. This proved to be interesting because metastatic melanomas have increased iron levels, which may or may not be responsible for signature variations.

The classical fields of chemistry (analytical, organic, physical, theoretical, inorganic, and biological) have become more integrated over time, making the labels themselves increasingly obsolete. To better label themselves, most chemists mix and match: “I’ve called myself at various times a ‘Bioanalytical Chemist,’ ‘Biophysical Organic Chemist,’ ‘Analytical Biochemist,’ ‘Organic Geochemist’ etc. to emphasize that the systems I’ve worked on, the techniques I’ve used, and the skills I’ve obtained are diverse and dependent on the project I’m defining.”

Glass says, “When I think that the names have gone a little haywire, I jokingly call myself an omni-chemist. Like most chemists I work on diverse array of projects that require techniques and knowledge from many fields.”

Addie Jackson interviewed Keely Glass and wrote this post as part of a Science Communication seminar led by NCSSM Dean of Science Amy Sheck.