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“The Big Three”: The mass spectrometer, the X-ray diffractometer, and the nuclear magnetic resonance (NMR) spectrometer

Chemistry prof. Joseph Tanski calls them “The Big Three”: The mass spectrometer, the X-ray diffractometer, and the nuclear magnetic resonance (NMR) spectrometer are key tools used by science students and faculty in class and in their research.

When the Bridge Science Laboratory opens this winter, Vassar will have state-of-the-art versions of all three instruments, thanks to more than $1 million in grants awarded to the college over the past decade by the National Science Foundation.

Chemistry profs Teresa Garrett and Joseph Tanski posing with their latest NSF-funded acquisition, a nuclear magnetic resonance (NMR) spectrometer

A single crystal X-ray diffractometer was acquired in 2005 through a pair of NSF grants written by Tanski totaling about $400,000. Associate prof. of chemistry Teresa Garrett secured a $389,180 grant in 2010 to purchase a mass spectrometer, and in August the college was awarded $289,000 to replace its outmoded NMR with a larger, more sophisticated device through a grant co-authored by Tanski and Garrett.

“We are now up to date on all three instruments for our chemistry labs,” says Garrett. “Having this equipment helped me secure funding for my own research, and because we are good stewards of the equipment we’ve acquired, we’re more likely to get more funding in the future.”

The single crystal X-ray diffractometer measures the diffraction pattern from a crystal, enabling researchers to determine the structure of the molecules that make up the crystal. “The X-rays hit the crystal and diffract, and by measuring the angle and intensity of the diffraction, you get a three-dimensional picture of how the atoms are arranged in the molecule,” Tanski explains.

Professor Tanski in 2006, posing with the newly acquired single crystal X-ray diffractometer

X-ray diffractometers are common in chemistry labs at major research universities, Tanski says, but they are usually off-limits to undergraduate students. At Vassar, chemistry students use the instrument in some of their classes and in their independent research. “This is a pretty special machine that enables our students here to do research that gets published,” he says. “This gives them a leg up when they get to graduate school.”

Garrett uses the mass spectrometer both as a teaching tool and for her own research on lipids and proteins.

Professor Garrett in her lab with the mass spectrometer behind her

 Samples are injected into the mass spectrometer and ionized with high voltage, enabling researchers to determine their molecular mass. The upgraded mass spectrometer that was acquired in 2010 can also be used to break the molecules into smaller fragments that can be measured and used to confirm a molecule’s structure. “This instrument was an upgrade – it measures mass with high accuracy and can be used to determine molecular structure,” she says. “It does everything we need it to do.”

The new NMR spectrometer, which will be installed in the Bridge Science Laboratory when it opens this winter, is also a major upgrade. “Most colleges have NMRs, but ours is bigger and better than most,” Tanski says. “It will give us better resolution, so it will be easier to determine the structure of molecules, and the calibration is automatic, which will really help. Manual calibration is tedious and inexact.”

Tanski and Garrett say a major reason why the NSF continues to fund major purchases for the Chemistry Department is that the college shares the equipment with faculty and students elsewhere. Tanski has collaborated on research projects using the X-ray diffractometer with faculty at Bard, Kenyon, Union, and Ithaca colleges and the University of Vermont, among others. Garrett has shared Vassar’s mass spectrometer with researchers at Marist College, Bard College and SUNY New Paltz in the Hudson Valley as well as Rutgers University in New Jersey and McMaster University in Canada, among others. Some researchers come to the Vassar campus to use the devices themselves, while others send samples of their research material to Tanski and Garrett and their students for analysis.

Gary Hohenberger, who coordinates major grant applications for the college, says such collaborations are a key factor in securing NSF funding. “We usually get more than 40 percent of the NSF grants we apply for every year, and that’s a lot for an undergraduate school,” says Hohenberger, director of corporate foundations and government relations. “It’s becoming more competitive every year, but Vassar continues to do well.”

This year, Vassar’s science program also received a major donation from a non-government source, IBM Corp. The firm gave the college an electron microscope, which will be installed in a special room built for the device in the basement of the Bridge building. IBM approached associate prof. of chemistry Christopher Smart about the donation because Smart and some of his students had been using the microscope in an IBM lab in Yorktown, NY, for several years.

“When our joint study agreement was winding down, “Our colleagues at IBM told me they’d be taking the microscope out of service and asked me if the college wanted it,” says Smart, who worked for IBM before he joined the Vassar faculty. “The retail price of a new electron microscope is more than $200,000, and while this one is about 25 years old, it performs all the necessary functions.”

A chemistry student adjusting the X-ray diffractometer

The Earth Science and Geography Department also obtained a grant from the NSF to purchase a new powder X-ray diffractometer in 2013. The device, which cost $90,000, is used to determine the composition of minerals in soil samples. “This device allows our undergraduate students to do advanced research,” says geology prof. Jeff Walker.

Tanski and Garrett say they expect Vassar to receive more sizeable grants in the future, enabling science faculty and students at Vassar to continue to do cutting-edge research. “Our track record in training our students and publishing the results of our research in scholarly journals speaks for itself,” Tanski says.

--Larry Hertz

Posted by Office of Communications Friday, September 11, 2015