University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Chemistry Letters

  • Publisher:
  • FAD Code: CHLT
  • CODEN: CMLTAG
  • ISSN: 0366-7022
  • Abbreviation: Chem. Lett.
  • DOI Prefix: 10.1246/cl
  • Language: English
  • Comments: Fulltext from 1972 V1

Citations 23

"Ink-jet Microchip Interface Between Liquid Flow And Flame-ionization Detector"
Chem. Lett. 2006 Volume 35, Issue 3 Pages 272-273
Takahide Nishiyama, Fumihiro Endo, Hiroko Eguchi, Jun Tsunokawa, Tatsuro Nakagama, Nobuko Seino, Masaki Shinoda, Takuya Shimosaka, Toshiyuki Hobo and Katsumi Uchiyama

Abstract: An ink-jet microchip interface between the continuous liquid flow and flame-ionization detector (FID) for gas chromatography (GC) has been developed. An ink-jet microchip for a conventional recorder was modified for the interface. When the interface was used for a flow-injection analysis (FIA) system with FID, 3.3 ng of the detection limit (S/N = 3) of ethanol in water was performed. Copyright © 2006 The Chemical Society of Japan.

"Highly Sensitive Flow Analysis Of Trace Level Arsenic In Water Based On Vaporization-collection In-line Preconcentration"
Chem. Lett. 2005 Volume 34, Issue 2 Pages 176-177
Kei Toda and Takashi Ohba

Abstract: Vaporization-collection in-line pre-concentration (VCIP) is proposed for simple and highly sensitive measurement of vaporizable water pollutants. In this work, VCIP has been applied to arsenic analysis to develop an instrument for use in the field. The signal is 200 times higher than with conventional direct injection. Low ppb levels of As can be analyzed automatically in one step. This method is expected to be applicable to the measurement of very low levels of other water vaporizable pollutants as well. Copyright © 2005 The Chemical Society of Japan.

"Microscale Absorption Procedure For Simple And Rapid Gas-liquid Extraction And Its Application To The Determination Of Nitrogen Dioxide In The Atmosphere Coupled With Microflow Injection Analysis"
Chem. Lett. 2001 Volume 30, Issue 4 Pages 318-319
Lan Ma, Mitsuko Oshima and Shoji Motomizu

Abstract: A simple and miniaturized flow-through gas absorbing unit (GAU) using a small volume of an absorbing solution (0.5 mL) was developed and applied to the determination of nitrogen dioxide (NO2) in the atmosphere. The measuring method was coupled with a microflow injection analysis system (µFIA) for a small sample size consumption. The absorption efficiency of NO2 in the GAU was improved by packing hydrophobic poly(tetrafluoroethylene) (PTFE) particles in the unit, and by using a triethanolamine aqueous solution (TEA, 2 g/L) as an absorbing solution: absorption efficiency was increased up to more than 95%. The absorbed NO2 was converted to NO3- and NO2-. The molar ratio was ascertained to be 1:1 by measuring the concentrations of NO2- and NO3- in the absorbing solution using µFIA. Nitrogen dioxide at concentrations above 10 ppb in the atmosphere could be determined by the proposed method.

"Metal-modified Diamond Electrode As An Electrochemical Detector For Glucose"
Chem. Lett. 2001 Volume 30, Issue 2 Pages 144-145
Ryuji Uchikado, Tata N. Rao, Donald A. Tryk and Akira Fujishima

Abstract: Nickel- and copper-modified diamond electrodes were fabricated in view of their application for carbohydrate detection. Both electrodes produced well-defined and reproducible voltammograms for I mM glucose in alkaline media. These electrodes exhibited excellent electrochemical stability with low background current for at least one week in a flow injection analysis system, indicating good adherence of the metal clusters to diamond. These results indicate the promising use of nickel-and copper-modified diamond electrodes for the detection of carbohydrates and amino acids.

"Mini-scale Solid-phase Collection And Concentration Of Ultra-trace Elements In Natural Waters For The Simultaneous Multielement Determination By Air-flow Injection/ICP-mass Spectrometry"
Chem. Lett. 2000 Volume 29, Issue 11 Pages 1338-1339
Mitsuko Oshima, Kyue-Hyung Lee, Yunhua Gao, and Shoji Motomizu

Abstract: A mini-scale solid-phase collection and concentration method for the multielement determination of ultra-trace rare earth elements (REEs) in natural water samples was developed by using a newly designed small-scale filtration apparatus. A small-size chelating resin disk (iminodiacetate type: IDA; 10 mum pore size; 5 mm diameter; 0.5 mm thickness) was used for high-enrichment pre-concentration of REEs and for elimination of alkali and alkaline earth metals in sample solutions. At pH 5.5, REEs in artificial river waters were quantitative ly collected on the chelating resin disk, and most of alkali and alkaline earth metals were removed. The REEs on the chelating resin disk were completely recovered by ultrasonication of the disk with 1 cm(3) or less of 0.1 mel L-1 nitric acid. A small amount (25 µL) of the concentrated sample solution was automatically injected and measured by inductively coupled plasma - mass spectrometry (ICP-MS) coupled with an airflow injection (AFI) system.
Preconcentration Extraction

"Electrochemical Detection Of Serotonin Using Conductive Diamond Electrodes"
Chem. Lett. 1999 Volume 28, Issue 11 Pages 1213-1214
Bulusu V. Sarada, Tata N. Rao, Donald A. Tryk, and Akira Fujishima

Abstract: The electrochemical detection of serotonin with highly B-doped diamond thin film electrodes was studied using flow injection analysis (FIA) with amperometric detection. The voltammetric behavior of diamond indicated low background current and a low tendency to adsorb the oxidative products on the electrode surface, in comparison to the glassy C electrode. An experimental amperometric detection limit of 10 nM (0.2 pmol) was obtained for the FIA technique, demonstrating that diamond is a stable and sensitive electrode for serotonin determination.

"Successive Flow Injection Determination Of Iron(III) And Copper(II) By Means Of The Effect Of Activators"
Chem. Lett. 1999 Volume 28, Issue 6 Pages 521-522
Tsuyako Watanabe, Norio Teshima, Makoto Kurihara, Shigenori Nakano, and Takuji Kawashima

Abstract: A novel flow injection (FI) photometric method has been proposed for the successive determination of iron(III) and copper(II). It is based on the effect of activators such as 1,10-phenanthroline and 2,9-dimethyl-1,10-phenanthroline (neocuproine) on iron-and copper-catalyzed oxidative coupling of p-anisidine with N,N-dimethylaniline in the presence of hydrogen peroxide. By injecting two activators, alternatively, into the FI system, iron(III) (50 -200 ng cm(-3)) and copper(II) (5 -20 ng cm(-3)) can be selectively determined.

"Bioelectrochemically Accelerated Microbial Conversion Of Nicotinic Acid To 6-hydroxynicotinic Acid On Microorganism-immobilized Column Electrolytic Flow System"
Chem. Lett. 1998 Volume 27, Issue 4 Pages 295-296
Masaki Torimura, Hideto Yoshida, Kenji Kano, Tokuji Ikeda, Toru Nagasawa, and Teruhisa Ueda

Abstract: Nicotinic acid (NA) is efficiently hydroxylated into 6-hydroxynicotinic acid (6HNA) by Pseudomonas fluorescens TN5-immobilized column electrolytic method using K3Fe(CN)6 as an extracellular electron transfer mediator, in which the conversion rate was sufficiently accelerated compared with the aerobic oxidation The NA conversion system was applied to the continuous-prodn. of 6HNA in 100% yield and the abs. determination of NA in flow injection anal.
Nicotinic acid Spectrophotometry Immobilized bacteria

"New Analytical Chemiluminescence System Using Peroxymonosulfate As Oxidant"
Chem. Lett. 1993 Volume 22, Issue 9 Pages 1575-1578
Yuji Makita, Hidetoshi Umebayashi, Takehiko Suzuki, Akio Masuda, Masaaki Yamada and Toshiyuki Hobo

Abstract: Details are given of a flow injection chemiluminescence method for the determination of metal ions. Sample solution was injected into a stream of water at pH 7.1, 2.1 or 2.3 for determination of Co2+, Fe2+ or VO2+, respectively. The carrier stream merged with a stream of 0.3 M Na2HPO4 (for Co2+), unbuffered water (for Fe2+) or 0.01 M NaHCO3 (for VO2+) which had previously merged with a stream of 0.2 M KHSO5 and the chemiluminescence of the mixture was recorded. The detection limits were 0.01, 0.2 and 0.6 µM for Co2+, Fe2+ and VO2+, respectively, but Co2+ and Fe2+ interfered in the determination of VO2+. The same flow system was also used to determine various organic compounds (details given).
Metals Cobalt(II) Iron(2+) Chemiluminescence Redox Interferences

"Steady-state Flow Analysis. A New Approach To Rapid And Sensitive Analysis For Long-period Reactions In Continuous-flow System"
Chem. Lett. 1993 Volume 22, Issue 5 Pages 877-880
Chongliang Zhang, Yoshio Narusawa and Shizuo Kitahama

Abstract: A new approach, called steady state flow analysis (SSFA), has been developed to improve the reproducibility, sensitivity and analytical speed for long period reaction in flow analysis systems. The new approach is based on parallel double-line FIA, stopped-flow FIA and steady state determinations. The apparatus consists of several parallel reaction coils and a multi-port valve which allow the reaction coils to be connected to the flow-through detector cell in sequence. The pulse signals obtained correspond to non-dispersion steady states. The effects of reaction coil length and flow rate on the peak height of the signal is investigated. An equation is developed which relates sampling frequency to the number of reaction coils and the reaction time. For example, if the apparatus has 12 reaction coils, for reaction times of 5, 10 and 20 min, the sampling rates are 120, 60 and 30 samples h-1 respectively.
Kinetic Steady state Sensitivity Stopped-flow

"Simultaneous Flow Injection Determination Of Vanadium(IV) And Vanadium(V) Based On Redox Reactions Of Vanadium(IV) With Iron(III) And Vanadium(V) With Iron(II) In The Presence Of 1,10-phenanthroline And Diphosphate"
Chem. Lett. 1992 Volume 21, Issue 11 Pages 2227-2230
Norio Teshima, Hideyuki Itabashi and Takuji Kawashima

Abstract: In the presence of 1,10-phenanthroline (I), Fe(III) is reduced by V(IV) to Fe(II) which forms a red complex with I producing an increase in absorbance (positive peak) at 510 nm. In the presence of diphosphate, Fe(II) is oxidized with V(V) which results in a decrease in absorbance (negative peak). By injecting I, sample solution [containing a mixture of V(IV) and V(V)] and diphosphate into a flow injection system (diagram given) in sequence, alternating positive and negative signals are obtained which correspond to the concentration. of V(IV) and V(V), respectively. The calibration graphs were rectilinear for 2 to 20 µM of V(IV) and V(V). A flow injection analysis (FIA) method is presented for simultaneous determinations of vanadium(IV) and vanadium(V) with photometric detection. It is based on redox reactions of vanadium(IV) with iron(III) and vanadium(V) with iron(II) in the presence of 1,10-phenanthroline (phen) and diphosphate (pyrophosphate), respectively. The proposed method makes it possible to observe bothpositive and negative FIA peaks corresponding to the concentrations. of vanadium(IV) and vanadium(V) alternatively.
Vanadium(IV) Vanadium(V) Spectrophotometry Redox Speciation

"Entrapment Of Glucose Oxidase In Silica Gel By The Sol - Gel Method And Its Application To A Glucose Sensor"
Chem. Lett. 1992 Volume 21, Issue 8 Pages 1615-1618
Yoshiro Tatsu, Keishi Yamashita, Muneaki Yamaguchi, Soichiro Yamamura, Hitoshi Yamamoto and Susumu Yoshikawa

Abstract: A flow injection sensor is described in which silica gel-entrapped glucose oxidase (prep. described) was held on the tip of an O electrode by means of nylon netting and a cellulose membrane. The flow cell was immersed in a water bath at 37°C. The sensor was used in the determination of glucose with a carrier stream (1 mL min-1) of sodium phosphate buffer of pH 5.1 and detection at -0.5 V. The calibration graph of integrated current was usable for up to 400 mg dl-1 of glucose.
Glucose Sensor Electrode Heated reaction Silica gel Immobilized enzyme Nylon

"Chemiluminescence Of Tryptophan With Electrogenerated Tris(2,2'-bipyridine)ruthenium(III)"
Chem. Lett. 1991 Volume 20, Issue 8 Pages 1373-1376
Kazuo Uchikura and Makoto Kirisawa

Abstract: Determination of tryptophan (I) and its related compounds was carried out in a two-channel FIA system equipped with a chemiluminescence detector. The method was based on the electrochemical oxidation of 0.24 M tris(2,2'-bipyridine)ruthenium(III) in 10 mM H2SO4 by reaction with I. The carrier solution consisted of a mixture of 10 mM H3PO4 - acetonitrile (1:1) to which a current of 80 µA was applied. The resulting orange chemiluminescence was measured. The effect of pH, flow rate and concentration. of reagent on the intensity was investigated. The detection limit of I was 0.1 pM; calibration graphs were rectilinear up to 200 pM. The method was also applied in the determination of other substituted indoles, but with inferior sensitivities.
Tryptophan Chemiluminescence Flow rate measurement Multichannel pH

"Online Elimination Of Electroactive Interferents For Flow-type Electrochemical Biosensor System"
Chem. Lett. 1991 Volume 20, Issue 5 Pages 849-852
Yusuke Okawa, Hiroyuki Kobayashi and Takashi Ohno

Abstract: A flow-through electrolytic cell containing a C felt working electrode separated from a Pt wire counter electrode by a Nafion membrane was combined with a glucose oxidase monolayer electrode in a flow injection analysis system (diagram given). The system was evaluated for the elimination of L-ascorbic acid (I) interferent in the determination of D-glucose. The elimination efficiency for I, as well as the biosensor response, were considerably increased by the addition of 0.1 M K3Fe(CN)6 to the carrier stream of 0.067 M-phosphate buffer (pH 6.4). Down to 1 mM glucose could be detected. The system was applied in the determination of glucose content in soft drinks; results agreed well with those of an enzyme-based colorimetric method.
Glucose Soft drink Electrode Electrode Sensor Buffer Interferences Nafion membrane

"Novel Flow Injection Method For Selective Spectrophotometric Determination Of Acetylcholine Using Thermochromism Of Ion Associates"
Chem. Lett. 1991 Volume 20, Issue 1 Pages 163-166
Tadao Sakai, Yun-hua Gao, Noriko Ohno and Nobuo Ura

Abstract: Samples (0.14 ml) containing acetylcholine (I) were injected into a flow injection system (illustrated) with a buffered (pH 11) carrier stream and a reagent stream (10 mM tetrabromophenolphthalein ethyl ester in dichloroethane) at 0.8 mL min-1. The temperature of the flow cell (illustrated) was 45°C, which reduced interference and improved recovery, and detection was at 610 nm. For 5 mM I, the coefficient of variation was 1.2% (n = 5); sample throughput was 36 h-1. The effects of different amines were investigated.
Acetylcholine Spectrophotometry Buffer Heated reaction Interferences Selectivity

"Simultaneous Determination Of Phosphate, Silicate And Arsenate By Online Column Flow Injection Analysis"
Chem. Lett. 1987 Volume 16, Issue 7 Pages 1367-1370
Yoshio Narusawa and Takahiro Hashimoto

Abstract: In the flow system described, the 20 µL sample is injected into a carrier mobile phase (0.5 mL min-1) containing 0.1 M KCl, 0.01 M NH3 and 1 mM Na2EDTA for sequential separation of the anions in a column (15 cm x 4.6 mm) of TSKgel SAX (5 µm), merging and reaction with a molybdate reagent in a coil (3 m x 0.5 mm) at 80°C and then with ascorbic acid reductant in a coil (4 m x 0.5 mm) at 80°C, followed by spectrophotometric detection at 810 nm. Operating ranges for detection and determination were 1 µM (0.55 ng of Si) to 2 mM for SiO32-, 5 µM (3.1 ng of P) to 0.5 mM for PO43-, and 2 µM (3.0 ng of As) to 0.2 mM for AsO43-; coefficient of variation were 3% except near the lower limits.
Arsenate ion Phosphate Silicate Spectrophotometry Heated reaction Multicomponent

"Eosin Y-sensitized Chemiluminescence Of 7,7,8,8-tetracyanoquinodimethan In Surfactant Vesicles For Determination Of Manganese(II) At Sub-nanogram Level By Flow Injection Method"
Chem. Lett. 1985 Volume 14, Issue 10 Pages 1597-1600
Masaaki Yamada, Satoru Kamiyama and Shigetaka Suzuki

Abstract: A flow stream (7 mL min-1) containing 40 µM-7,7,8,8-tetracyanoquinodimethan, 4 mM didodecyldimethylammonium bromide and 0.6 mM eosin Y (C. I. 45380) is merged with an equal flow of 0.01 M NaOH, and 20 µL of Mn(II) solution (containing 0.01 to 10 ng of Mn) is injected. A 260-fold enhancement of the chemiluminescence occurs rapidly due to Mn(II) catalysis without need for a long reaction coil and is measured at 345 nm. Of 26 other species (injected as 0.1 mM solution) only Fe and Mg gave appreciable signals.
Manganese(II) Chemiluminescence Catalysis Interferences

"Chemiluminescence Method For Selective Determination Of Iron(II) And Chromium(III) With Single-reaction System"
Chem. Lett. 1985 Volume 14, Issue 6 Pages 801-804
Masaaki Yamada, Atsuko Sudo and Shigetaka Suzuki

Abstract: A continuous-flow analytical system is described in which, for determination of Fe(II), a 1 mM solution of Brilliant Sulfoflavine (C. I. Acid Yellow 7) in 1 mM NaOH in aqueous 80% acetonitrile is mixed with an equal flow of aqueous 0.09% H2O2, and, after passage through a 2-m reaction coil, is mixed with the analyte solution and the emitted chemiluminescence is measured at 520 nm. For determination of Cr(III), the solution containing Cr(III) is mixed with the aqueous 0.09% H2O2 before passage through the coil and with the dye solution afterwards. Logarithmic calibration graphs were rectilinear over three decades, with lower detection limits of 1 nM for Fe(II) and 30 nM for Cr(III). No significant interference was shown by ~40 foreign species tested for either determination.
Iron(2+) Chromium(III) Chemiluminescence Interferences

"Flow Injection Analysis Of α-amino Acids By The Chemiluminescence Method"
Chem. Lett. 1985 Volume 14, Issue 3 Pages 341-342
Tadashi Hara, Motohiro Toriyama, Takashi Ebuchi and Masakatsu Imaki

Abstract: The catalytic effect of Cu(II) upon the chemiluminescence reaction between luminol and H2O2 is quantitatively inhibited by the presence of an α-amino-acid. Sixteen amino-acids tested all showed this property but to varying extents. As an example, a rectilinear calibration graph (log. peak area vs. log. concentration.) was drawn for determination of 1 µM to 0.1 mM L-aspartic acid with a detection limit of 2.7 ng injected. The present method is less sensitive than the dansylation method of Honda et al. (Anal. Chem., 1983, 55, 940), but avoids the need for derivatization.
Amino acids, α Aspartic acid Chemiluminescence Catalysis

"Flow Injection Analysis With An Amperometric Detector Utilizing The Redox Reaction Of Iodate Ion"
Chem. Lett. 1984 Volume 13, Issue 6 Pages 873-876
Sanae Ikeda, Hiromu Satake and Yasuyuki Kohri

Abstract: Solutions of 0.1 mM KIO3 - 0.42 M KBr and 1 M H2SO4, fed at 0.35 mL min-1, were blended and then mixed with a water stream (1.14 mL min-1) into which 20 µL samples were injected and fed via a 3.5-m reaction coil to an amperometric detector with a platinum-wire indicator electrode maintained at +0.6 V vs. a silver-tubing electrode. The system was calibrated by use of 0.1 to 1 mM hydrazine, and could then be used to determine hydrazine and L-ascorbic acid in the range 0.2 to 0.8 mM and L-cysteine in the range 0.2 to 0.6 mM; coefficient of variation were ~0.4 to 0.7%.
Hydrazine Ascorbic acid Cysteine Amperometry Electrode Redox

"Measurement Of Enzymic Activity Of Inorganic Pyrophosphatase For Pyrophosphate By Flow Injection Analysis"
Chem. Lett. 1983 Volume 12, Issue 9 Pages 1433-1436
Norimasa Yoza, Hisanobu Hirano, Mayumi Okamura, Shigeru Ohashi, Yukio Hirai and Katsumaro Tomokuni

Abstract: The sample, containing phosphate, was injected into a stream of water (1 mL min-1), which was then merged with a stream of reagent (1 mL min-1) containing 0.03 M-Mo(VI), 0.3 M H2SO4 and 0.01 mM KH2PO4 (the phosphate was added to stabilize the baseline). After passing through a reaction coil (5 m x 0.5 mm; 30°C), the absorbance of the resulting solution was measured. The coefficient of variation was <1%. Phosphate could be determined in the range 0.01 to 1 mM. The method could be used to determine phosphate produced by the action of inorganic pyrophosphatase on pyrophosphate, and thus to assay the enzyme.
Phosphate Enzyme, pyrophosphatase Biochemical analysis Spectrophotometry Heated reaction Enzyme

"Chemiluminescent Determination Of Traces Of Copper(II) By Flow Injection Method"
Chem. Lett. 1982 Volume 11, Issue 11 Pages 1747-1748
Masaaki Yamada and Shigetaka Suzuki

Abstract: Chemiluminescence in conjunction with flow injection analysis is described for the determination of traces of Cu(II) by means of the FMN-hydrogen peroxide-phosphate buffer system. This permits the determination of Cu(II) more selectively than any other chemiluminescent system with a detection limit of 30 pg.
Copper(II) Chemiluminescence Selectivity

"Flow Injection Analysis Of Inorganic Ortho- And Polyphosphates Using Ascorbic Acid As A Reductant Of Molybdophosphate"
Chem. Lett. 1980 Volume 9, Issue 5 Pages 499-502
Yukio Hirai, Norimasa Yoza and Shigeru Ohashi

Abstract: A spectrophotometric method based on the formation of heteropoly blue complex was applied to the flow injection analysis of inorganic ortho-and polyphosphates such as diphosphate and triphosphate. Ascorbic acid was used to reduce molybdophosphate. Total amounts of inorganic ortho-and polyphosphates could be determined at a sampling rate of 45 samples/h with a relative standard deviation of less than 1%.
Phosphate Polyphosphates Water Spectrophotometry Heated reaction