contents
http://pubs.acs.org/ac ISSN 0003-2700
February 1, 2002 / Vol. 74, No. 3
features 70 A
COVER STORY 78 A
The Physics of Laser Ablation in Microchemical Analysis. Does a simple preparation method for analyzing subpicomolar quantities sound too good to be true? Richard Russo, Xianglei Mao, and Samuel Mao at Lawrence Berkeley National Laboratory explain the theory behind laser ablation, a technique that is gaining popularity for solid-state sampling applications. Plastic Advances Microfluidic Devices. DNA and pharmaceutical researchers are always on the lookout Poof! for cheaper, faster, and more accurate methods for processing 70 A growing numbers of analytical samples. Travis Boone, Z. Hugh Fan, Herbert Hooper, Antonio Ricco, Hongdong Tan, and Stephen Williams at ACLARA BioSciences reveal how fabricating microfluidic devices out of plastic can cut production costs, speed up analytical turnover time, and reduce cross-contamination between samples.
news 59 A
AnalyticalCurrents Deducing protein–protein interaction networks. a Protein complexes without solvent. a Roughing it in the real world. a Color-changing fluoride sensor. a Watching viruses infect cells. a Positively identifying Gram-negative bacteria. a CNMs—New chemically selective filters? a Dynamic probing of metal surfaces. a NIRS is great for libraries. a Detecting “seeds” of Alzheimer’s disease.
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Research Profiles A colorimetric assay for the ages. Early Romans laid the groundwork for colloidal surface plasmon resonance. a Tweaking entropy’s edge. Separate double-stranded, 200-kilobase pair DNA fragments in just 30 min. a Electrochemistry, endocrine disruptors, and the environment. A new competitive assay may help elucidate low-level chemical effects.
Molecular metal surfaces. 62 A
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The new heavy weight contender? 87 A
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Governm entand Society Standardizing food analysis.
68 A
People David Nelson receives Pittcon Heritage Award. a SACP 2002 Starter Grant Award.
departments 53 A
Editorial The Strength of Multiple Choices for Chemical Research. Having multiple agencies support basic research may be “wasteful” and “inefficient” at times, but centralizing funding into a single agency could be much worse.
55 A
In AC Research
87 A
ProductReview The SFC Comeback. Cheryl Harris finds that pharmaceutical applications are revitalizing supercritical fluid chromatography.
93 A
AC W ebw orks CE on the Web. Steve Miller examines what an emerging member of the analytical family of methods offers online.
Plastic, disposable, economical. 78 A
Assays from ancient Rome? 64 A
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Books and Softw are A Starting Point for DNA Microarrays. Roy Tan of ACLARA BioSciences reviews DNA Arrays: Methods and Protocols.
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M eetings Pittcon 2002. a Conferences.
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New Products
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AC Research Contents
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AC Research
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AuthorIndex
Point-and-click to CE. 93 A
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The Strength of Multiple Choices for Chemical Research T
he diversity of agencies and foundations that provide support for basic research in U.S. educational institutions is an enormous strength of U.S. analytical chemistry and chemical sciences in general. The National Science Foundation awards peer-reviewed grants for investigations of basic analytical chemistry and provides a separate proposal track for young investigators. The ACS Petroleum Research Fund similarly supports the basic chemistry efforts of young and established investigators through separate competitions. The federal “mission” agencies have more targeted agendas, which are nonetheless still quite broad: The Department of Energy aids research ranging from the analysis of energy production by-products to new materials useful in transportation and communication; the National Institutes of Health support research that is relevant to understanding the chemistry of human functioning and disease; the research offices of the Defense agencies— Navy, Army, and Air Force—fund research supporting their measurement and materials needs; the Environmental Protection Agency targets analytical chemistry that monitors the environment and its health; and the Food and Drug Administration provides some support for the analytical chemistry of edible and pharmaceutical products. There also exists a substantial body of nonprofit foundations (e.g., the Research Corporation and the Dreyfus Foundation) with awards for research in colleges and teacher-scholars in universities. Private industry supports college and university research in varied ways and for different reasons. And I could go on and on. There is never enough support, but what is available comes from diverse sources, has many objectives, and funds a range of investigators. Periodically, one hears cries for the consolidation, standardization, and streamlining of agency systems for research support and in the manner in which proposals are evaluated. Often, these cries are in the name of “eliminating waste and inefficiency”. Let’s face it. When you explore the unknown, you get lost a lot. Basic research, by its very essence, is intrinsically wasteful and inefficient. In basic investigations, truly important discoveries of new ways to measure or make chemi-
cals come in fits and starts, by brilliance or simple serendipity, and with no foreordained schedule. There are an awful lot of experiments in between those discoveries that yield either no progress or serve to fill in important gaps in our knowledge. These are actually, in volume, the larger body of basic research progress. Imagine, if you will, a universe in which all of the above federal agencies have been combined into a single super agency. Imagine what would follow: homogenization of the kinds of ideas and proposals that are viewed with approval; infighting among agency managers who support different missions or goals—and remember that the researcher is in the line of fire; instability in research directions and progress resulting from year-by-year and director-by-director prioritization of research directions to be supported; and even the possibility of political influence being focused on a single bureaucracy to limit research into areas viewed as distasteful or not sufficiently moral. The separate routes that support the current system ensure the existence of a substantial breadth of research directions and make political tampering with those directions much more difficult. This discussion is yet another reason to recite my frequent refrain: Research chemists have a continuing obligation to explain the nature of their research to the lay public and to public officials whenever an opportune moment arrives. Keep handy some examples of the products of basic research and their benefits to human society. That’s really not so hard. For example, just remember the three P’s: polymers, pH, and pharmaceuticals.
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