BRIEFS
Kinetic Modeling of Fast Atom Bombardment Spectra of Glycerol-Diethanolamine Mixtures
98
A kinetic model based on high-pressure gas-phase ion-mole cule reactions gives good agreement with experimental FAB spectra of solutions of diethanolamine in glycerol. Jan Sunner, Angelina Morales, and Paul Kebarle*, Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2 Anal. Chem., 60 (1988)
Detection of Ethylene Glycol Dinitrate Vapors by Ion Mobility Spectrometry Using Chloride Reagent Ions 104 Ethylene glycol dinitrate (EGDN) vapors can be detected by ion mobility spectrometry and chloride reagent ions as (EGDN-C1) - ion clusters. The detection limit for a purified air sample is 30 pg, and the optimum operating temperature is 75 °C. A. H. Lawrence* and Pavel Neudorfl, Unsteady Aerodynamics Laboratory, National Aeronautical Establishment, National Re search Council, Ottawa, Ontario K1A 0R6, Canada Anal. Chem., 60 (1988)
Characterization and Selection of Electrolyte Systems for Isotachophoresis of Anions by Cluster Analysis
120
The leading electrolyte system with pH 3 and one with pH between 6 and 10 are found, based on a hierarchical and a nonhierarchical clustering procedure, to be the most favor able binary combination for identification purposes. Terna ry combinations are also selected. Additional systems do not increase the identification power. Ernst Kenndler* and Gregor Reich, Institute for Analytical Chemistry, University of Vienna, Waehringerstrasse 38, A-1090 Vienna, Austria Anal. Chem., 60 (1988)
Effects of Dilution of Poly(ethylvinylbenzene-divinylbenzene) Adsorbent on the Adsorption of Aliphatic, Alicyclic, and Aromatic Hydrocarbon Adsorbates from Effective Zero to Finite Surface Coverage 124 Relative retentions and heats of adsorption agree to within experimental error with those observed previously for the bulk title adsorbent. N. M. Djordjevic and R. J. Laub*, Department of Chemistry, San Diego State University, San Diego, Calif. 92182 Anal. Chem., 60 (1988)
Cluster Ion Formation under Laser Bombardment. Studies of Recombination Using Isotope Labeling 110 Ion formation by recombination in the laser-induced plasma is observed directly by laser microprobe MS in the produc tion of cluster ions from NiS particles deposited on isotopically enriched sulfur thin films. Inga H. Musselman, Richard W. Linton*, and David S. Simons, Department of Chemistry, University of North Carolina, Chapel Hill, N.C. 27514, and Center for Analytical Chemistry, National Bureau of Standards, Gaithersburg, Md. 20899 Anal. Chem., 60 (1988)
Determination of Dihydroqinghaosu in Blood by Pyrolysis Gas Chromatography/Mass Spectrometry 115 Dihydroquinghaosu, a major metabolite of the antimalarial drug artesunic acid, is assayed by quantitation of its major pyrolysis product with an internal standard method in the low nanogram-per-milliliter range. Anthony D. Theoharides*, Michael H. Smyth, Robert W. Ashmore, James M. Halverson, Zhong Ming Zhou, William E. Ridder, and Ai Jeng Lin, Department of Pharmacology, Division of Experimental Therapeutics, Walter Reed Army Institute of Re search, Washington, D.C. 20307-5100 Anal. Chem., 60 (1988)
Anodic Characterization of Mercury Microelectrodes in Electrolytes at the Micromolar Level
131
Mercury microelectrodes based on platinum disks of either 1- or 12.5-μπι radius are characterized anodically in various electrolytes at the micromolar level. Zbigniew Stojek, Department of Chemistry, Warsaw University, Pasteura 1, 02-093 Warsaw, Poland, and Janet Osteryoung*, De partment of Chemistry, State University of New York at Buffalo, Buffalo, N.Y. 14214 Anal. Chem., 60 (1988)
Determination of Cephalosporins and Decomposition Products by Liquid Chromatography with Indirect Electrochemical Detection 136 Cephalosporins are determined in standard solutions with detection limits of 0.4-3 ng and a precision of 1.5%. The method is applied to the determination of cefotaxime and its main metabolite in serum and urine, and selectivity is im proved compared with that obtained with UV detection. H. Fabre and W. Th. Kok*, Laboratory for Analytical Chemistry, University of Amsterdam, Nieuwe Achtergracht 166,1018 WV Am sterdam, The Netherlands Anal. Chem., 60 (1988)
* Corresponding author 64 A · ANALYTICAL CHEMISTRY, VOL. 60, NO. 2, JANUARY 15, 1988
BRIEFS Measurement of Liposome-Released Ferrocyanide by a DualFunction Polymer Modified Electrode 142 Liposome-encapsulated potassium ferrocyanide is mea sured by differential pulse voltammetry following release by surfactant or complement lysis. The electrode used is modi fied with an anion-exchange polymer film to provide preconcentration of the released ferrocyanide and to protect it from lipid-protein fouling. Rosanne M. Kannuck and Jon M. Bellama, Department of Chemistry and Biochemistry, University of Maryland, College Park, Md. 20742, and Richard A. Durst*, Center for Analytical Chemis try, National Bureau of Standards, Gaithersburg, Md. 20899 Anal. Chem., 60 (1988)
Simultaneous Determination of Glucose, Fructose, and Sucrose in Mixtures by Amperometric Flow Injection Analysis with Immobilized Enzyme Reactors 147 Response of the sensors is linear between 2 Χ 1 0 - 5 and 1 X 10~3 M. The precision (C.V.) for 10 successive injections at the 1-mM level is better than 1.8% for glucose, 1.8% for fructose, and 1.6% for sucrose. Application of the system to foods is also described. Kiyoshi Matsumoto*, Hideaki Kamikado, Hiroaki Matsubara, and Yutaka Osajima, Department of Food Science and Technol ogy, Faculty of Agriculture, Kyushu University 46-09, Hakozaki, Higashi-ku, Fukuoka 812, Japan Anal. Chem., 60 (1988)
Voltammetric Determination of Traces of Nickel(ll) with a Medium Exchange Flow System and a Chemically Modified Carbon Paste Electrode Containing Dimethylglyoxime 151 Submicromolar nickel(II) is detected after 30 s accumula tion in the deoxygenated system. The electrode is stable for more than 4 h. Karsten N. Thomsen and Lars Kryger*, Department of Chemis try, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Den mark, and Richard P. Baldwin, Department of Chemistry, Univer sity of Louisville, Louisville, Ky. 40292 Anal. Chem., 60 (1988)
Spectroelectrochemical Response and Optical Geometry Optimization of Thin-Layer Flow Detectors with Long Optical Path Lengths: Theory 156 Steady-state current and absorbance responses are quanti tatively modeled for thin-layer spectroelectrochemical flow cells. Effects on absorbance of the spatially inhomogeneous sample distribution are treated, and optimum optical geom etries are predicted, based on signal-noise considerations. Lawrence E. Fosdick and James L. Anderson*, Department of Chemistry, The University of Georgia, Athens, Ga. 30602 Anal. Chem., 60 (1988)
Spectroelectrochemical Response and Flow Hydrodynamics in Thin-Layer Flow Detectors with Long Optical Path Lengths and Fiber-Optic or Slab Waveguide Coupling 163 The absorbance and current responses of rectangular, thinlayer spectroelectrochemical flow cells with long optical path lengths show good agreement with theoretical predic tions and are used to assess fully developed vs. developing or stagnating laminar flow. Lawrence E. Fosdick and James L. Anderson*, Department of Chemistry, The University of Georgia, Athens, Ga. 30602 Anal. Chem., 60 (1988)
X-ray Photoelectron Spectroscopy of Silica Surfaces Treated with Polyfunctional Silanes 169 Results of XPS studies of silanized surfaces indicate that base catalysts modify the surface chemistry of reactions involving multifunctional silanes. The extent of surface cov erage is also base-catalysis-dependent. Krishna M. R. Kallury, Ulrich J. Krull, and Michael Thomp son*, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 1A1, Canada Anal. Chem., 60 (1988)
Evaluation of a Nitrosyl-Specific Gas-Phase Chemiluminescent Detector with High-Performance Liquid Chromatography 173 The detector responds linearly to nitrated polycyclic aro matic hydrocarbons between the concentration range of 10 and 1000 ng per compound injected. The HPLC/CD system provides for isocratic and gradient elution in both normal and reversed-phase operation. Albert Robbat, Jr.*, Nicholas P. Corso, and Tyng-Yun Liu, Chemistry Department, Tufts University, Medford, Mass. 02155 Anal. Chem., 60 (1988)
Determination of Ammonium Ion by Fluorometry or Spectrophotometry after On-Line Derivatization with 0-Phthalaidehyde
175
The limit of quantitation for the method is 2 picomoles NH 4 + , and the reproducibility is ±0.3%. An assay time of 1 min is required. Sham S. Goyal*, Donald W. Rains, and Ray C. Huffaker, De partment of Agronomy and Range Science/Plant Growth Laborato ry, University of California, Davis, Calif. 95616 Anal. Chem., 60 (1988)
66 A · ANALYTICAL CHEMISTRY, VOL. 60, NO. 2, JANUARY 15, 1988
BRIEFS ENVIRONMENTAL SCIENCE & TECHNOLOGY
ES&T
Correspondence Exchange of Comments on the Role of the Interface in Solvent Extraction Processes 180 Henry Freiser, Strategic Metals Recovery Research Facility, Department of Chemistry, University of Arizona, Tucson, Ariz. 85721, and Frederick F. Cantwell, Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2 Anal. Chem., 60 (1988)
Simultaneous Enhancement of Fluorescence and Thermal Lensing by Reversed Micelles
182
Chieu D. T r a n , Department of Chemistry, Marquette University, Milwaukee, Wis. 53233 Anal. Chem., 60 (1988)
Influence of Porphyrin Structure on Anion Selectivities of 185 Manganese(lll) Porphyrin Based Membrane Electrodes N. A. Chaniotakis, A. M. Chasser, and M. E. Meyerhoff*, Department of Chemistry, The University of Michigan, Ann Arbor, Mich. 48109, and J. T. Groves, Department of Chemistry, Princeton University, Princeton, N.J. 08544 Anal. Chem., 60 (1988)
Technical Notes The premiere research publication in the environmental field. Environmental science continues to be one of the fastest growing fields. And ES&T has grown right along with it! ES&T continues to give you the practical, hard facts you need on this s c i e n c e . . . covering research, techniques, feasibility, products and services. Essential reading for environmental scientists both in the business and academic world . . . ES&T has increased its emphasis on peerreviewed research dealing with water, air, and waste chemistry in addition to adding critical reviews of important environmental science issues—all relevant to understanding the management of our natural environment.
Fabrication of Platinum-Disk Ultramicroelectrodes
188
C. D. Baer*, N. J . Stone, and D. A. Sweigart*, Department of Chemistry, Brown University, Providence, R.I. 02912 Anal. Chem., 60 (1988)
Automated Cryogenic Collection of Carbon Dioxide for Stable Isotope Analysis and Carbon-14 Accelerator Mass Spectrometry Dating 191 C.A.M. Brenninkmeijer, Institute of Nuclear Sciences, Department of Scientific and Industrial Research, Private Bag, Lower Hutt, New Zealand Anal. Chem., 60 (1988)
Correction. Ion-Pair Chromatographic Determination of Anions Using an Ultraviolet-Absorbing Co-Ion in the Mobile Phase 192 Brian A. Bidlingmeyer*, Carmen T. Santasania, and F. Vincent Warren, Jr., Waters Chromatography Division of Millipore Corporation, 34 Maple Street, Milford, Mass. 01757 Anal. Chem., 60(1988)
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(800) 424-6747 68 A · ANALYTICAL CHEMISTRY, VOL. 60, NO. 2, JANUARY 15, 1988
