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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Biochemical analysis

Classification: Biochemical analysis

Citations 28

"The Bio-analytical Potential Of Flow Injection Analysis"
Anal. Chim. Acta 1983 Volume 145, Issue 1 Pages 117-124

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P. J. Worsfold

Abstract: The suitability of flow injection analysis for the study of biochemically specific interaction is discussed. The possibilities are illustrated by the analytical performance of two particular systems: a manifold incorporating an immobilized glucose oxidase coil for the determination of β-D-glucose in blood and a stopped-flow manifold used to monitor a model immunoprecipitin interaction between concanavalin A and yeast mannan.
d-Glucose Blood Immobilized enzyme Stopped-flow Review

"Optimization Of Peroxidase Immobilization And Of The Design Of Packed-bed Enzyme Reactors For Flow Injection Analysis"
Anal. Chim. Acta 1983 Volume 145, Issue 1 Pages 87-99

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Bo Olsson and Lars Ögren

Abstract: Packed-bed reactors containing horse radish peroxidase were optimized for use in flow injection systems. The most active and stable immobilizations were produced by azo linkage to porous glass. The influence of pore and particle diameter as well as pH of immobilization, number of coupling sites, and enzyme purity were studied. The reactor behavior could be accurately described by a theory derived on the assumptions of first-order kinetics. The effects of internal and external mass transfer resistances were studied and the rate constants were evaluated. Design criteria for analytical reactors are discussed. A small particle diameter is shown to be of utmost importance in order to achieve low dispersion with fixed levels of back-pressure and conversion.
Glucose Hydrogen peroxide Oxygen Apparatus Immobilized enzyme Optimization Reactor Review Theory

"Polymer-membrane PH Electrodes As Internal Elements For Potentiometric Gas-sensing Systems"
Anal. Chim. Acta 1983 Volume 155, Issue 1 Pages 11-20

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W. N. Opdycke, S. J. Parks and M. E. Meyerhoff

Abstract: The use of a pH-responsive polymer, based on tridodecylamine incorporated in a PVC matrix, was studied for the fabrication of low-cost NH3- and CO2-sensing electrodes for, e.g., detection in biochemical analysis. Miniature static gas sensors were constructed either (i) with or (ii) without internal reference solution In (i) an earlier design (cf. Meyerhoff et al., Anal. Abstr., 1983, 44, 3D29) was used, and in (ii) the membrane was coated directly on to a graphite rod. Under optimum conditions such static sensors exhibited rectilinear responses with slopes of 48 to 62 mV per decade, and potentials were reproducible to within ±1.5 mV at gas concentration. >1 mM. For automated continuous-flow systems, tubular forms of the polymer-membrane electrodes and a simple flow-through gas-dialysis arrangement were used (cf. Anal. Chem., 1981, 53, 992). The polymer-based sensors provide an attractive alternative to gas-sensing devices based on conventional glass pH electrodes.
Ammonia Carbon dioxide Gas sensor Dialysis Gas diffusion

"Determination Of Fungal α-amylase By Flow Injection Analysis"
Anal. Chim. Acta 1984 Volume 158, Issue 2 Pages 375-377

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Preben W. Hansen

Abstract: A manual iodine - starch method has been adapted for use in the analysis of broths from Aspergillus oryzae fermentations. The absorbance of the residual starch - iodine complex was measured at 570 nm following degradation of starch by the enzyme at 37°C and pH 4.7. Rectilinear calibrations were obtained over the range 0.01 to 0.1 amylase units mL-1. Results agreed well for the determination of α-amylase in diluted culture broth by flow injection analysis and by the manual method, but the flow injection method affords a sampling rate of 80 h-1, ~5 times that possible by the manual method.
α-Amylase Fermentation broth Method comparison Indirect Complexation

"Biochemical Data-processing With Microcomputers. 3. Online Data Acquisition From A Continuous-flow Analyser"
Anal. Chim. Acta 1984 Volume 161, Issue 1 Pages 393-396

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Michael G. Gore and Ian G. Giles

Abstract: A program written in BASIC, and developed for use on a Commodore PET 3000 (but easily modified for use with other microcomputers), is presented. Data from three or four analytical channels are sampled, and the amount of substance present is calculated by reference to a pre-defined calibration graph; the results of all tests relating to one specimen are collated and printed together, even when the analytical methods require different times for completion, and the program includes routines to store the collected data on disc or cassette tape. The algorithm of the program used for peak-height determination and collation of data is described.
Computer Signal processing

"Immobilized Enzymes In Clinical And Biochemical Analysis. Applications To The Simultaneous Determination Of Acetylcholine And Choline And To The Determination Of Lipids"
Anal. Chim. Acta 1988 Volume 214, Issue 1-2 Pages 173-186

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M. Masoom

Abstract: A flow injection analysis system was used with a 10 µL sample-injection loop, one or more immobilized-enzyme reactor columns and an amperometric (for choline or acetylcholine) or a commercial (HPLC) potentiometric detector (for lipids). In the former system, acetylcholinesterase and choline oxidase were immobilized by glutaraldehyde cross-linking to controlled-pore glass and packed into columns (3 cm x 2.5 mm) that were operated at 25°C. The amperometric detector consisted of two Pt electrodes (6 mm x 3 mm) sandwiched between Perspex sheets and separated by a 1-mm-thick sheet of silicone rubber, and the carrier stream (0.5 mL min-1) was 0.1 M phosphate buffer adjusted to pH 8.2. Rectilinear calibration graphs for 10 to 100 µM-choline and -acetylcholine were obtained. For determination of phospholipids, the appropriate phospholipase and glycerol-3-phosphate oxidase were used in the included reactor columns with a carrier stream (1.5 mL min-1) of pH 7.0 containing 20 mM barbitone sodium(I), or a column of co-immobilized phosphatase - choline oxidase was used with a buffered carrier stream of 0.1 M Tris (pH 7.5) or 20 mM I (pH 6.5), Triton X-100 (0.2 or 0.3%) and 0.4 mM ZnCl2 or 30 mM CaCl2. Calibration graphs for phosphatidylcholine were rectilinear for 1 to 10 mM or 50 to 800 mg l-1.
Choline Acetylcholine Phospholipids Blood Controlled pore glass Immobilized enzyme Surfactant Triton X Simultaneous analysis

"Potential Of The Flow-gradient Function In Flow Injection Analysis With A Multifunction Pump Delivery System"
Talanta 1988 Volume 35, Issue 6 Pages 425-430

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Jun'ichi Toei

Abstract: The use in flow injection analysis of successive positive and negative flow gradients followed by a positive flow gradient combined with stopped-flow gives high sensitivity for peak-height measurement and good reproducibility. The technique was applied in the enzymatic determination of glucose with satisfactory results, and may be used in biological studies.
Glucose Enzyme Gradient technique Stopped-flow

"Study And Analytical Application Of Rare Earth Inhibition Of Laccase"
Talanta 1994 Volume 41, Issue 5 Pages 735-738

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Cai Ruxiu, Huang Houping, Wang Guangfei, Lin Zhixin and Zeng Yun'e

Abstract: Laccase is a multi copper-containing oxidase. The effects of metal ions on the laccase-catalyzed redox reaction of 5,6-dibromo-2,3-dicyanohydroquinone to 5,6-dibromo-2,3-dicyanosemiquinone were studied. Rare-earth ions (Y, Sc, La, Lu) strongly inhibited the reaction. The degree of inhibition of La(III) on laccase activity was proportional to the concentration of La. A stopped-flow enzyme-catalyzed analytical kinetic method for determination of rare earths was proposed. The degree of inhibition of La(III) on the laccase-catalyzed reaction was linear from 0.033-0.2 ppm of La. The detection limit was 0.033 ppm and the RSD was 5.3% (n = 11). The method was used to determine rare-earth elements in water.
Metals, rare earth Environmental Stopped-flow Enzyme Kinetic Catalysis

"Bioelectrochemical Determination Of Citric Acid In Real Samples Using A Fully Automated Flow Injection Manifold"
Analyst 1997 Volume 122, Issue 10 Pages 1101-1106

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Mamas I. Prodromidis, Stella M. Tzouwara-Karayanni, Miltiades I. Karayannis and Pankaj M. Vadgama

Abstract: An enzymatic method for the determination of citric acid in fruits, juices and sport drinks is proposed. The method is based on the action of the enzymes citrate lyase, oxaloacetate decarboxylase and pyruvate oxidase, which convert citric acid into H2O2 with the latter being monitored amperometrically with a H2O2 probe. The enzymes pyruvate oxidase and oxaloacetate decarboxylase were immobilized. A multi-membrane system, consisting of a cellulose acetate membrane for the elimination of interferants, an enzymatic membrane and a protective polycarbonate membrane were placed on a Pt electrode and used with a fully automated flow injection manifold. Several parameters were optimized, resulting in a readily constructed and reproducible biosensor. Interference from various compounds present in real samples was minimized. Calibration graphs were linear over the range 0.01-0.9 mM pyruvate, 0.015-0.6 mM oxaloacetate and 0.015-0.5 mM citrate. The throughput was 30 samples h-1 with an RSD of 1.0% (n = 8); the mean relative error was 2.4% compared with a standard method. The recovery was 96-104%. A 8-10% loss of the initial activity of the sensor was observed after 100-120 injections.
Citric acid Fruit Fruit Sport drink Automation Interferences Immobilized enzyme Optimization Method comparison Standard method

"Microporous Membrane Flow Cell With Non-immobilized Enzyme For Chemiluminescent Determination Of Glucose"
Anal. Chem. 1982 Volume 54, Issue 11 Pages 1698-1701

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