compared with the 3vv- and lzo-um microelectrOQco UocQ lii earner work. 1 ney used the technique to map the current distributions over platinum QISK electrodes. The ac distribution measured in solution was compared with analytical solutions and computer simulations. 1 ne spatial resolution of the probe was defined by varying the height of the probe and the distance between the microelectrodes and was found to be 30-40 um. (J. Electrochem. Soc. 1997,144,1957-65)
Raman for air monitoring Continuous emissions monitoring (CEM) will eventually be required at all coalpowered electric plants. Praveen C. Kumar and Joseph A. Wehrmeyer of the University of Missouri-Columbia have suggested that Raman spectroscopy could be used for simultaneous CEM measurements of CO, NO, and S02. They used a Nd:YAG laser as the excitation source. A liquid-nitrogen-cooled CCD was used to collect the spectra with an integration time of 200 s. The long integration time increased the interference from cosmic rays. The gases were placed in a sample cell that mimicked stack conditions and were maintained at 1 atm. The detection limits were 100 ppm for S02, 250 ppm for CO, and 250 ppm for NO. (Appl. Spectrosc. 1997,51,849-55)
CCC of peptides Because there is no solid support in the separation column, countercurrent chromatography has some advantages over conventional chromatography, such as high sample recovery and minimal denaturation. A variation of the technique called pH-zone refining CCC uses two reagents, one acting as a retainer in the stationary phase and the other as an eluter in the mobile phase. Advantages include increased sampleloading capacity, elution of highly concentrated fractions, and detection and concentration of minor components.
Elution profile of three dipeptides with a broad range of hydrophobicities under four sets of experimental conditions. (Adapted with permission. Copyright 1997 Elsevier Science.)
tial of an adverse effect must receive FDA approval prior to implementation. This rule applies to those products that Biotechnology were previously called "well-characterproduct rule hits the ized" biotechnology products (Anall Chem. 1996,68,674 A-77 A), although street FDA has determined that it is more approThe U.S. Food and Drug Administration (FDA) has issued thefinalrule for making priate to indicate specific products than to use such a broad term. Such products changes to an approved application for include recombinant DNA-derived prospecified biotechnology and biological products (Fed. Regist. 1997, 62, 39890- teins and complexes or conjugates of drugs with monoclonal antibodies. 903). Changes fall into one of three categories based on their potential to have an These changes are part of FDA's onadverse effect on the "identity, strength, going efforts to fulfill the Clinton Adminisquality, purity, or potency of the product, tration's "Reinventing Government" initiaas they may relate to the safety or effective. The rule takes effect Oct. 7. tiveness of the product." Celia Henry Changes that have a minimal effect on the safety and effectiveness can be reported to FDA in an annual report Changes that EPA pushes PBMS have a moderate potential to have aa affect on the safety and efficacy must be reported approach New Text to FDA 30 days before distributton. Changes If all goes as planned, this month each of that are deemed to have a substantial poten- EPA's assistant administrators will submit a GOVERNMENT
Yoichiro Ito and Ying Ma at the National Institutes of Health used this technique to separate underivatized peptides by introducing an ion pair reagent, di-(2-ethylhexyl) phosphoric acid (DEHPA), into the stationary phase. To optimize the separation, they found that the DEHPA concentration and the hydrophobicity of the solvent system needed to be adjusted according to the hydrophobicities of the analytes in question. They separated gram quantities of bacitracin complex and bovine insulin. (J. Chromatosr. A 1997 771 81-88)
plan to the Environmental Monitoring Management Council on how their program office will implement the performancebased monitoring system (PBMS) approach to environmental monitoring. What is signiiicant is that the deadline was imposed by Fred Hansen, the deputy administrator of EPA in a memo circulated in June. Moreover, the memo sets a September e998 9eadline for implementation of PBMS with the warning that any extension will be granted only under exceptional circumstances. PBMS gives analysts greater freedom in selecting a method for an environmental measurement as opposed to prescriptive methods that detail each step in an analytical procedure. Numerous groups have pushed EPA to adopt the PBMS approach, and a program to introduce PBMS methods is already well underway within the agency (Anal. Chem. 1996, 68, 733 A-37 A)) However, ,ome had feared that the effort would fail without high-level support in the agency. Hansen's
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News
another interesting problem. In a recent case, the Bureau had to determine whether pieces of "crack" cocaine came from a single cake. To make crack, cocaine HC1 is baked with sodium bicarbonate and solvent and formed into cakes, which are broken LABORATORY New Text when cooled. The pieces were seized by the investigaPROFILE tors and fit together like a puzzle. IR spectroscopy re~ The science of law vealed a match based on fibers that had fallen into the and order Analyzing one of thousands of samples. mixture before it cooled From standard breathalyzer tests to specimen is logged in at the crime DNA matches, state crime laboratories Polyethylene was also detected because scene until it or its analysis is brought must do it all—on a limited budget and polyethylene shreds were incorporated out in trial. When a blood or body fluid into the batch as plastic bags of cocaine under constant scrutiny by the police, stain is cut from a piece of clothing, were cut open the courts, the prosecution, the defense, the news media, and the public. Many of the bureau's remaining 8000 or one analyst witnesses another cutting it out and documents the procedure. The New Jersey State Police Forensic so cases involve "secondary transfer"— Generally the person who performs an Science Bureau, with four regional something from the perpetrator's environlaboratories, has responsibility for ana- ment sticks to him or her and is then trans- analysis follows the evidence all the lyzing all municipal, county, and state ferred to the victim or the crime scene. For way through and is responsible for drug evidence and breathalyzer samevidence from break-ins, the labs use FT-IR testifying in court. ples, as well as all physical evidence Another crucial area of responsibiland scanning electron microscopy with an from crimes ranging from homicides ity for the labs is bringing criminal inenergy-dispersive detector to analyze the to suspected arsons. With New Jerelements in paint scrapings from screwdriv- vestigators and theirfieldtechnicians sey's large urban population and the up to date on sampling and storage ers and other tools. In one assault case, expectation that almost techniques. Resources to perform analplastic shavings found on the victim were brings multiple specimens requiring analyzed by transmission FT-IR microspec- yses, including the amount of available sample, are limited; and not all analymultiple analyses the burden quickly trometry and GC pyrolysis. The evidence adds UD led police back to an individual who worked ses are relevant or necessary to solving the case. For instance, now that Last year, with fewer than 100 labo- in an auto body shop and WHS covered in blood and semen can be analyzed by shavings from his work. ratory staff, the bureau handled eviPCR rather than enzyme tests, differdence from more than 37,000 criminal Validation of analytical methods can ent preservatives are needed. cases, including nearly 29,000 drug become a significant issue for the bureau In fact, the labs in the last few years cases, says Thomas Brettell, the buin court. In the recent Megan Kanka case, have moved significantly into the area of reau's assistant chief forensic scientist. the child sexual assault/murder that reDNA analysis by PCR One bureau case For routine drug evidence, which dom- sulted in "Megan's Law,, the prosecution involved DNA extracted from the saliva inates the caseload, the bureau has a contested the bureau's hair andfiberevion the back of a postage stamp. A citicourt-mandated turnaround time of 15 dence linking Jesse Timmendiquas to zen had complained of receiving threatdays. Thus, the laboratories limit the Megan Kanka, citing the Daubert rullng ening letters. Using the PCR results in analysis to the minimum needed to that specifies that scientific analyses use further investigation, police showed that substantiate each charge usually pre- established points of comparison that are the citizen was the perpetrator. sumptive screening color, followed by acceptable in the profession. "Hair eviconfirmatory automated GC/MS. dence is more subjective than many other So far, the bureau labs perform DQUnusual drug cases do crop up. For comparisons and requires greater training alpha and polymarker locus matches, to interpret," Brettell explains. but Brettell says they have just received example, appropriate GC/MS stana National Institute of Justice grant to dards for anabolic steroids, popular The bureau labs use numerous methevaluate short tandem repeat analysis with bodybuilders, are hard to come ods in hair and fiber comparisons, includ(STR), a method he thinks is set to reby. Steroids typically come as injecting polarized light microscopy and FT-IR place the older methods in many state able mixtures of four or five different microspectrometry to identify and compare crime labs once they validate it. "Multihormones. Moreover, they are often dyes. Because the labs use only wellmanufactured overseas, and containers validated and published methods, the court plex DNA and STR methods are definitely on their way. CE isn't ready yet, are usually in foreign languages and allowed this critical evidence into trial. but I think you're going to see it in the frequently mislabeled. Brettell says the greatest protection for the bureau labs' work in court is maintain- future for DNA analysis." Tracing street drugs, usually dirty Deborah Noble ing the chain of custody from the time a mixtures, back to clandestine labs is
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support, says Michael Duff, executive director of the Analytical Instrument Association, is reason for optimism. According to Richard Reding of EPA's Office of Water, Hansen's memo doesn't affect any of the work that has already gone on but rather "lays down the gauntlet" In fact, the Office of Water has taken the approach of introducing "flexibility" in its methods rather than a complete PBMS approach, and Reding doesn't see anything in the memo that conflicts with that philosophy. He also warns that any changes must still conform to each program's legislative mandates, and thus full implementation could occur after the 1998 deadline. In his memo, Hansen also calls for an integrated agencywide approach to environmental monitoring and a blueprint for investment in new and innovative technologies Alan Newman
PEOPLE
Graduate fellowship awards Eleven analytical chemistry graduate students have been selected by the ACS Division of Analytical Chemistry to receive fellowships for either the academic year ($14,000 paid over nine months) or for th< summer ($4650 paid over three months). The program encourages basic research in analytical chemistry and recognizes its future leaders.
Emily Niemeyer of the State University of New YorkBuffalo (Frank V. Bright). Niemeyer's research focuses on molecular-scale interactions and solute solvation in supercritical fluids and the enect of gas sorption on polymer dynamics. Her fellowship is sponsored by duPont. Stephen Sum of the University of Delaware (Steven D. Brown). Sum is developing a signal correction method that removes instrument and physical sample effects from analytical measurements, allowing for the transfer of multivariate calibration between instruments. His fellowship is sponsored by Perkin Elmer. Kami Thoen of Purdue University (Hilkka Kenttamaa).Thoen's research focuses on organic tandem mass spectrometry. Her fellowship is sponsored by Eli Lilly. Summer fellowships
Full-year fellowships
Craig Aspinwall of the University of Florida (Robert T. Kennedy). Aspinwall is working on developing and characterizing analytical methods for studying insulin secretion from single pancreatic beta cells. His fellowship is sponsored by Eastman Chemical. Kai Hu of the University of Texas (Allen J. Bard). Hu is using atomic force microscopy for characterizing surface charges of semiconductor nanoparticles. His fellowship is sponsored by Procter & Gamble.
Guodong Chen of Purdue University (R. Graham Cooks). Chen's research includes the kinetics of dissociation of cluster ions in mass spectrometry. His fellowship is sponsored by Dow Chemical. Peng Chen of the University of Indiana (MilosV. Novotny). Chen is working on glycoconjugate analysis and isolating and characterizing the fluorescent pigment associated with oxidative stress and aging using various techniques. His fellowship is sponsored by the Society of Analytical Chemists of Pittsburgh (SACP).
Rebecca Garden of the University of Illinois Gonathan V. Sweedler). Garden uses mass spectrometry to profile peptides within individual cells. Her fellowship is sponsored by the R. W. Johnson Pharmaceutical Research Institute. Paul Schnier of the University of California-Berkeley (Evan R. Williams). Schnier's research includes mechanistic studies of ionization and dissociation of large ions with the goal of developing mass spectrometry methods to rapidly characterize large biomolecules. His fellowship is sponsored by SACP. Irina Serebrennikova of the University of Calgary (Canada) (V. I. Birss). Serebrennikova is studying the electrocatalytical and nanostructural properties of Ni-Co oxide films. Her fellowship is sponsored by SACP. Mark Vitha of the University of Minnesota (Peter Carr). Vitha's research includes understanding the fundamental chemical forces governing the interactions of small molecules using surfactant micelles and thermodynamic and spectroscopic methods. His fellowship is sponsored by SACP. Honorable mentions are Susan L R. Barker of the University of Michigan (Raoul Kopelman), Indu Kheterpal of the University of California-Berkeley (Richard A. Mathies), and Lei Liu of the University of Pittsburgh (Sanford A Asher). Nominations
Applications are being accepted for the 1998-99 Division of Analytical Chemistry Graduate Fellowships. Five full-year and six summer fellowships are expected to be awarded.
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