Contents
FEATURES 175 A On the Cover. Chemical Imaging for Raman Spectroscopy. Raman chemical imaging has recently emerged as a powerful technique for routinely analyzing the chemical architecture of materials. Michael D. Schaeberle of the National Institutes of Health, Hannah R. Morris of Duquesne University, John F. Turner of Carnegie Mellon University, and Patrick J. Treado of ChemIcon compare scanning and imaging spectrometer approaches and describe several applications of the technique. 183 A Membrane Preconcentration CE. Because of the small capillary volumes, only a limited amount of sample can be Chemical images with Raman. Page .75 A. loaded into a capillary electrophoresis system. This, in turn, means that concentration limits of detection are typically rather poor. Qing Yang, Andy J. Tomlinson, and Stephen Naylor of the Mayo Clinic and Foundation introduce a new approach for preconcentrating samples prior to separation by CE, which improves detection limits, especially for biologically derived analyte mixtures. NEWS 167 A Analytical Currents Go for the gold. • Subattomole detection of catecholamines. • Studying protein Preconcentrating samples for CE. Page 183 A. ionization with charge ladders. • Controlling fluid motion and position. • New spray chamber for USN. • MALDI spectra reflect solution phase. • Cancer cell profiles with MALDI-TOFMS. • Simplified ESI spectra. • The origin of limestone fluorescence. • Redox switching. 171 A Science Sorting cells. Tried-and-true methods for sorting cells are not easily miniaturized. Xiao-Bo Wang and colleagues at the University of Texas' M. D. Anderson Cancer Center demonstrate dielectrophoretic/gravitationalfield-flowfractionation, which separates cells using levitation, in a narrow chamber. • Living sensors for saccharides. Current methods for detecting sugar stereoisomers are not easy or quick. Sylvia Daunert and her colleagues at the University of Kentucky demonstrate a simpler approach using genetically engineered E. colt, which respond to the sugar L-arabinose by producing an easily observed fluorescent protein. • Probing the plume. Just what is happening in the electrospray plume, and how does it affect the electrospray mass spectrum? Kelsey Cook and his co-workers at the University of Tennessee-Knoxville and Oak Ridge National Laboratory use laser-induced fluorescence to probe the electrospray plume chemically and spatially. 172 A Business Perkin-Elmer to sell Analytical Instruments Division. 173 A Government and Society NELAC prepares for implementation. • Comparability protocols ease changes. Do MALDI spectra reflect solution phase? Page 169 A. 174 A People Beckman receives NAS honor. • Keene P. Dimick nominations. • SACP starter grant award. 'This article is also available on the Web at http://pubs.acs.org, under "Hot Articles".
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Analytical Chemistry News & Features, March 1, 1999
ANALYTICAL C H E M S T R Y MARCH 1, 1999/VOL 71 NO. 5 ANCHAM 149 A-222 A/911-1092 (1999) ISSN 0003-2700
DEPARTMENTS 153 A Editorial The scientific method. Chemists have a set of mental reflexes that are the scientific method, but it is occasionally good to articulate what the ideal scientific reflexes involve. 155 A Letter to the Editor Artifact formation of methylmercury in sediments.
159 A In AC Research 1 9 1AFOCUS Pinning down PCR. Widespread interest in gene quantitation and high1
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Taking the measure of quantitative PCR. Page 191 A.
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reaction back in the spotlight. 197 A Product review Electrospray in flight. Orthogonal acceleration brings the advantages of time of flight to electrospray. 202 A Meetings ACS Spring National Meeting in Anaheim, CA. • Association of Biomolecular Resource Facilities meeting in Durham, NC. • Conferences. • Short course. 2 0 9 A A/C WebWorks A course of one's own: Distance learning. Ray Dessy looks at how education and training courses can be carried over the Internet. Electrospray combined with time-of-flight MS. 2 1 2 A Books and Software Page 197 A. Welcome to biosensors. Introduction to Bioanalytical Sensors is reviewed by Li Sun of Texas A&M University. • Worldwide textbook? Analytical Chemistry textbook is reviewed by Thomas J. Wenzel of Bates College. • GC practtcal advice. Basic Gas shromatography is reviewed by Mary A. Kaiser os DuPont. • Books received. • Software released. 217 A New Products 220 A Information
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Author Index
Registered in U.S. Patent and Trademark Office © Copyright 1999 by the American Chemical Society
Analytical Chemistry News & Features, March 1, 1999 151 A
