BRIEFS
Square Wave Anodic Stripping Voltammetry at the Mercury Film Electrode: Theoretical Treatment 386
Oxidation of Dopamine and 4-Methylcatechol at Carbon Fiber Disk Electrodes 405
Numerical calculations show that the differential current voltammograms are symmetrical, and the peak potential shifts to more negative potentials with decreasing film thick ness parameter. S. P. Kounaves, J. J. O'Dea, P. Chandresekhar, and Janet Osteryoung*, Department of Chemistry, State University of New York at Buffalo, Buffalo, N.Y. 14214 Anal. Chem., 59 (1987)
The current-time and current-potential responses of dopa mine and 4-methylcatechol are shown to be different. The adsorption of dopamine and dopamine-o-quinone to the microelectrode is demonstrated. Adrian C. Michael and Joseph B. Justice, Jr.*, Department of Chemistry, Emory University, Atlanta, Ga. 30322 Anal. Chem., 59 (1987)
Iridium-Based Small Mercury Electrodes
Determination of Amino Acids at Subfemtomole Levels by HighPerformance Liquid Chromatography with Laser-Induced Fluorescence Detection 411
389
Small iridium disks provide an insoluble, wettable substrate for hemispherical mercury electrodes. Some cyclic linear scan and stripping experiments are described to present the behavior of this type of electrode. Janusz Golas, Zbigniew Galus, and Janet Osteryoung*, Depart ment of Chemistry, State University of New York at Buffalo, Buffa lo, N.Y. 14214 ' Anal. Chem., 59 (1987) Direct Determination of Arsenite by Differential Pulse Polarography in the Presence of Lead(Il) and Thallium(l)
Detection limits for amino acids derivatized with 2,3-naphthalenedialdehyde are in the subfemtomole range. The results are ~ 3 orders of magnitude better than earlier reported results using the o-phthalaldehyde reagent. Mark C. Roach and Marlin D. Harmony*, Department of Chem istry and Center for Bioanalytical Research, University of Kansas, Lawrence, Kan. 66045 Anal. Chem., 59 (1987)
393
Arsenite is determined in the presence of up to 250 ppm Pb(II) and T1(I). The standard deviation is 4 ppb based on eight pairs of data. Margaret A. Reed and Richard J. Stolzberg*, Department of Chemistry, University of Alaska, Fairbanks, Alaska 99775-0520 Anal. Chem., 59 (1987) Determination of Surface Hydroxyl Groups on Glassy Carbon with X-ray Photoelectron Spectroscopy Preceded by Chemical Derivatization 396 The hydroxyl content of the glassy carbon samples is in the 1-10 mol% range. The analytical integrity of the analysis scheme is substantiated by using a model phenoxy resin of known structure. W. G. Collier and T. P. Tougas*, Department of Chemistry, Uni versity of Lowell, Lowell, Mass. 01854 Anal. Chem., 59 (1987) Plutonium and Uraniam Ion Determination and Differentiation Based on Twin Electrode Flow Coulometry 400 Flow coulometry, using twin-column electrodes connected in series, is used to determine 10~5 to 5 X 10~2 M Pu(III), Pu(IV), Pu(VI), TJ(IV), and U(VI) in a nitric acid solution. Hisao Aoyagi and Zenko Yoshida*, Analytical Chemistry Labora tory, Japan Atomic Energy Research Institute, Tokai, Ibaraki 319Ί1, Japan, and Sorin Kihara, The Institute for Chemical Research, Kyoto University, Uji-shi, Kyoto 611, Japan Anal. Chem., 59 (1987)
Characterization of Thin-Layer Chromatographically Separated Fractions by Fourier Transform Infrared Diffuse Reflectance Spectrometry 415 The method is based on the transfer of material from the TLC plate to a potassium chloride pellet, followed by exami nation using diffuse reflectance FT-IR. John M. Chalmers*, Moray W. Mackenzie, and John L. Sharp, Imperial Chemical Industries PLC, Petrochemicals and Plastics Division, Research and Technology Department, P.O. Box 90, Wil ton, Middlesbrough, Cleveland TS6 8JE, England, and Roger N. Ibbett, School of Chemical Sciences, University of East Anglia, Norwich NR4 7TS, England Anal. Chem., 59 (1987) High-Performance Liquid Chromatography with Supersonic Jet/Laser Fluorometric Detection 419 Anthracene derivatives are separated by HPLC and intro duced into a continuous-flow supersonic jet nozzle. The de tection limit for anthracene is 40 ng, which is similar to reported detection limits for naphthalene derivatives using GC with supersonic jet-fluorometric detection. Totaro Imasaka, Noriyuki Yamaga, and Nobuhiko Ishibashi*, Faculty of Engineering, Kyushu University, Hakozaki, Fukuoka 812, Japan Anal. Chem., 59 (1987)
* Corresponding author 118 A · ANALYTICAL CHEMISTRY, VOL. 59, NO. 3, FEBRUARY 1, 1987
