contents
http://pubs.acs.org/ac ISSN 0003-2700
May 1, 2001 / Vol. 73, No. 9
features 256 A
COVER STORY 266 A
Investigating Protein Structure and Dynamics by Hydrogen Exchange MS. Complete characterization of a protein requires understanding its function, structure, and dynamics. Fortunately, different protein structures undergo hydrogen/deuterium exchange at different rates, which has become a powerful means to study structure and Characterizing proteins by hydrogen exchange. dynamics. John Engen and David Smith of the University of Ne256 A braska–Lincoln and the University of Nebraska Medical Center describe models for interpreting hydrogen exchange results, introduce relevant examples with small and large proteins, and discuss the relative merits of NMR and MS for detecting the exchange. Ion Chromatography Retrospective. It began with a seminal 1975 paper and developed quickly because of strong commercial interests. Paul Haddad of the University of Tasmania (Australia) reviews the history of ion chromatography and speculates on where the technique is headed.
news 243 A
Analytical Currents Separating mixtures using fluorous tags. The whole proteome picture. In vivo NMR. Raman studies SAMs. “Shear” SECM know-how. Following dynamic changes. Protein orientation sleuths. Detecting fuel traces in blood. Tuning in to electronic molecular analysis. Two species, or not two species? Organic fluorine in humans. Total-analysis “taste” chip. Cleaving digestion-resistant proteins. Bacteria help FT-IR hunt down toxins.
250 A
Research Profiles Profiling enzymes to diagnose genetic disease. Even in the age of high-powered genetic screening labs, enzyme analysis plays a crucial role in the study of biological systems. Quantitative proteomics goes global.. By breaking proteins down into manageable pieces, researchers have been able to identify and quantify peptides by LC/MS and LC/MS/MS.
“Shear” SECM know-how. 245 A
234 A
A N A LY T I C A L C H E M I S T R Y / M A Y 1 , 2 0 0 1
contents
Ion chromatography—where it’s been, where it’s going. 266 A
252 A
Meeting News Blood-based prion test. ESI quantifies glycan moieties. Thermo Electron paints New Orleans red. Richard Kniss calls it quits. Varian “bears” it all at Pittcon.
253 A
Business 900-MHz NMR is here.
Analytical chemistry for nonchemistry science majors. 275 A
departments 237 A
Editorial Undergraduate Research Secrets Rediscovered. An old idea is finding new converts, but what are the “secrets” of the undergraduate research experience?
239 A
In AC Research
275 A
AC Educator Analytical Chemistry for Nonchemistry Science Majors.
279 A
Product Review XPS Up Close. XPS instruments have followed chemistry to smaller and smaller scales.
284 A
Books and Software
285 A
Meetings HPLC 2001
287 A
New Products
1C
AC Research Contents
1917–2151
AC Research
2152
Author Index
XPS goes for smaller and smaller. 279 A
Total-analysis “taste” chip. 248 A Cover Image ©Hamid Ghanadan/GH Multimedia 2001 M A Y 1 , 2 0 0 1 / A N A LY T I C A L C H E M I S T R Y
235 A
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e d i to ri a l
Undergraduate Research Secrets Rediscovered T
he past several years have seen a number of professional society articles and educational symposia espousing the merits of the undergraduate research (UGR) experience. Federal agencies have promoted grants programs aimed at encouraging UGR. My institution even recently opened an Office for Undergraduate Research. I’m sorry to pour rain on this parade but UGR is an old concept that has long been part of the fabric of teaching chemistry undergraduates within numerous departments. I had a small research project when I was an undergraduate, and my very first laboratory worker at the University of North Carolina was an undergraduate. I don’t think this is atypical for chemistry professors. Many companies have long sponsored summer UGR internships. UGR has been around for so long because it is an important and effective teaching tool. The recent promotion of UGR is a rediscovery of its importance, and its new devotees are most welcome. Just what are the “secrets” of the UGR experience? The first and foremost is that students learn to think independently in the context of a laboratory experiment. The independence comes in stages for the student. At the beginning, the student learns to design a laboratory experiment to explore a hypothesis or question, without the crutch of a laboratory manual. The research literature is little help in this regard; the vast majority lack sufficient detail to educate the typical undergraduate. The help comes from other students working in that laboratory or from the professor. A second level of independent thinking begins when the experiment doesn’t work! That failure is the grist of meaningful research can be a shock; learning analysis of failure and redesign is the next step. Further learning comes as results accumulate and the professor asks, “What do your results
mean?” When the first glimmer of understanding arrives— maybe with a little help from the professor—the undergraduate gains the first real pleasure of discovery, with the hopedfor reaction: “This is fun!” Then the undergraduate learns that “understanding” is not enough; one must challenge this understanding with further experiments to ascertain whether it is real or an illusion. Some will perceive that I have, in part, just described the classic scientific method. This is a wonderful thing to teach an undergraduate, and UGR is an ideal vehicle. I believe that the project chosen for UGR is less significant for the undergraduate than the actual learning process. However, the nature of the chemical project is important for stimulating student interest. That interest is often promoted by a project that relates to a societal need, an environmental problem, or a major current trend in chemical research. Selecting a project for a student is tricky, because his or her intellectual skills and stage of development must match its demands. If a mismatch is perceived, a strategic withdrawal should be considered that would not damage the student’s self-confidence. Undergraduates can be drawn to a UGR experience by the cynical desire to get a good recommendation letter, by curiosity, by the value that top graduate schools place on it, or by degree requirements. Whatever the circumstance, faculty and industrial scientists should treasure the opportunity to introduce young men and women to the same pleasures of discovery that led us all to become professional scientists.
M A Y 1 , 2 0 0 1 / A N A LY T I C A L C H E M I S T R Y
237 A
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