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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Cellulose acetate

Classification: Membrane -> Cellulose acetate

Citations 15

"Solute Transfer In Online Analytical Flow-through Dialyzers"
Anal. Chim. Acta 1985 Volume 167, Issue 1 Pages 111-122
Bo Bernhardsson, Eduardo Martins and Gillis Johansson

Abstract: Mass transfer in infinite parallel-plate dialysers is investigated for plug-flow, laminar-flow and mixing-cup models with co-flow between the sample and detector streams. Theoretically derived results for the three models are compared with experimental results obtained for the dialysis of Zn(II) across a cellulose acetate membrane. Agreement is fairly good, but errors are caused by differences in hydrostatic pressures on either side of the membrane and by stresses causing membrane bulging.
Zinc(II)

"Flow Injection Determination Of Glutathione With Amperometric Monitoring Of The Enzymatic Reaction"
Anal. Chim. Acta 1988 Volume 214, Issue 1-2 Pages 415-419
Ikuo Satoh, Shuji Arakawa and Akira Okamoto

Abstract: Gluthathione sulfydryl oxidase was immobilized (described) on to Eupergit-C (oxiran - acrylic beads; 100 to 200 µm diameter) and the preparation was packed into a plastic column (2.2 cm x 7.1 mm) which was incorporated into a flow injection system (illustrated) for indirect determination of glutathione. The flow-through amperometric detector comprised a cellulose acetate membrane-covered Pt anode and a Ag - AgCl reference electrode. Glutathione sample solution (0.2 ml) was introduced into the enzyme column at 30°C via a rotary injection valve, the carrier solution was 0.1 M potassium phosphate buffer (pH 7) containing 0.1 M KCl and the peak current arising from oxidation of H2O2 was measured. The calibration graph was rectilinear for 0.5 to 1.0 mM glutathione and the coefficient of variation (n = 10) was 2%.
Glutathione Amperometry Electrode Electrode

"Effect Of Whole Blood And Plasma On The Permeability Of Glucose Through Different Cellulose And Cellulose Acetate Membranes"
Anal. Chim. Acta 1990 Volume 231, Issue 2 Pages 165-173
Lars Risinger, Thomas Buch-Rasmussen, Gillis Johansson

Abstract: The transfer of glucose (I) from whole blood, plasma and aqueous standards through different membranes for use in biosensors was carried out with use of a flow injection system (diagram given) incorporating a flow-through dialysis cell that contained the membrane being studied. Detection was with use of a glucose dehydrogenase enzyme reactor and a graphite electrode at 0 mV vs. Ag - AgCl. The membranes studied were: cellulose acetate; Spectra/por 4 (mol. wt. cut off = 12,000 to 14,000; Spectrum Medical Industries, Los Angeles, CA); Spectra/por 6 (mol. wt cut off = 1,000) and cellulose acetate Cuprophan (mol. wt cut off = 5,000). Theoretical models are proposed for the effect of plasma viscosity and haematocrit on glucose transfer rate. Lower membrane permeability resulted in less dependence on haematocrit and smaller differences between results in aqueous solution, plasma and whole blood.
Glucose Blood Plasma Whole Sensor

"Amperometric Determination Of Glucose In Undiluted Food Samples"
Anal. Chim. Acta 1991 Volume 242, Issue 1 Pages 91-98
A. Amine and G. J. Patriarche, G. Marrazza and M. Mascini

Abstract: A sensor is described for determination of glucose. It involves glucose oxidase immobilized on to a cellulose acetate membrane through glutaraldehyde bonding. The membrane is placed over the Pt electrode of a H2O2 sensor. By placing a silanized polycarbonate membrane over the enzyme layer, the rectilinear range of the calibration graph was extended to higher concentration. The variation in response was studied as a function of pore size of the polycarbonate membrane. Response was approximately even from pH 4 to 8. The sensor was used in a flow injection system to determine 1 M glucose in soft drinks at a sampling rate of 60 h-1, and without the need for sample dilution. The coefficient of variation was 1.8% (n = 16) for 0.4 M glucose.
Glucose Soft drink Amperometry Electrode Electrode

"Amperometric Bienzymic Sensor For Aspartame"
Analyst 1997 Volume 122, Issue 5 Pages 487-490
D. Compagnone, D. O'Sullivan and G. G. Guilbault

Abstract: The cited sensor was fabricated by covalent immobilization of alcohol oxidase and α-chymotrypsin on to a polycarbonate membrane via glutaraldehyde. A cellulose acetate membrane was applied over the immobilized enzymes and used to attach the assembly to the surface of a Pt electrode. Amperometric measurements of aspartame (I) were performed in 0.1 M phosphate buffer of pH 7.5 with the Pt electrode polarized at +650 mV vs. Ag/AgCl. Calibration graphs were linear from 1-750 µM I using batch and flow-through methods, and up to 1 mM I using a flow injection method. Detection limits were 0.2-1 µM; RSD were 1.8-4% (n = 10). Different strategies for eliminating interfering compounds, including the use of an additional alcohol oxidase/catalase membrane and signal subtraction using an alcohol electrode, were employed. The sensor was applied to various foods; recoveries were 95-106%. An amperometric enzyme electrode for the determination of aspartame was developed by covalent immobilization of alcohol oxidase and α-chymotrypsin. A platinum based hydrogen peroxide electrode was used as the detector. Excellent sensitivity was obtained using batch, flow-through and flow injection methods with detection limits of 2 x 10^-7, 4 x 10^-7 and 10^-6 mol L-1, respectively. Different strategies for eliminating interfering compounds, including the introduction of an additional alcohol oxidase-catalase membrane and signal subtraction using an alcohol electrode, were employed. A recovery study on seven food samples was carried out and the results were satisfactory.
Aspartame Food Amperometry Sensor Electrode Electrode

"Asymmetric Carbonate Ion-selective Cellulose Acetate Membrane Electrodes With Reduced Salicylate Interference"
Anal. Chem. 1993 Volume 65, Issue 21 Pages 3151-3155
Kang Shin Lee, Jae Ho Shin, Sang Hyun Han, Geun Sig Cha, Doo Soon Shin, and Hai Dong Kim

Abstract: The asymmetric electrodes were prepared as described by Cha and Meyerhoff (Talanta, 1989, 36, 271). The hydrophilic layer, formed by direct base hydrolysis of one side of an unplasticized cellulose triacetate membrane, faced the sample solution, and the selective layer, incorporating 1-butyl-4-(trifluoroacetyl)benzene, tridodecylmethylammonium chloride and plasticizer [bis-(2-ethylhexyl) sebacate or adipate], was fused to the other side of the membrane. The internal filling solution was aqueous 0.1 M NaH2PO4/0.1 M Na2HPO4/0.01 M NaCl, and a double-junction Ag/AgCl electrode was used as the external reference electrode. The response of the asymmetric membranes, used in wall-jet configuration for detection in FIA, to small anions, including carbonate, was virtually unchanged compared with that of unmodified carbonate-selective cellulose triacetate-matrix or PVC-matrix membranes, but the response to salicylate and other larger anions was lower and also very slow. When the asymmetric membrane electrode was used to determine 25 mM CO2, no interference was caused by up to 1 mM salicylate. The electrode was also used in a static arrangement to determine total CO2 in blood serum.
Carbon dioxide Serum Human Electrode Electrode

"Determination Of Mercury(II) Traces In Drinking Water By Inhibition Of An Urease Reactor In A Flow Injection Analysis (FIA) System"
Fresenius J. Anal. Chem. 1997 Volume 357, Issue 6 Pages 752-755
Renbing Shi, K. Stein, Georg Schwedt

Abstract: The immobilization of urease on to polyacrylamide gel was carried out by a modification of a previous method (Stein and Schwedt, Vom Vasser, 1992, 79, 211). Acrylamide (50 mg) with 5% NN'-methylene bisacrylamide was dissolved in 0.5 mL phosphate buffer of pH 7 then 330 iu urease was dissolved in the resultant solution. Then 7 µL NNN'N'-tetramethylene diamine/ammonium peroxodisulfate (2:5) was added. This reaction mixture was poured on to a cellulose acetate membrane between two glass plates. After 30 min, the plates were separated and the enzymatic membrane was cut into pieces (1 cm diameter). A piece of membrane was rolled up and set in a glass column (45 x 2 mm i.d.). This urease reactor was integrated into an FIA system (schematic and details given). The measurement parameters are tabulated. Potentiometric measurements were made using an Ingold LOT 453 S-7 pH electrode. Calibration graphs were linear from 2-20 µg/l Hg(II); RSD was 1.4% (n = 5) for 2 µg/l Hg(II). A sample frequency of 7/h was achieved. The method was applied to the analysis of potable water; results were comparable with those obtained by a commercial system.
Mercury(II) Water Potentiometry Electrode

"Amperometric Determination Of Lactic Acid. Applications On Milk Samples"
Anal. Lett. 1988 Volume 21, Issue 5 Pages 727-740
Pilloton, R.;Nwosu, T.N.;Mascini, M.

Abstract: A H2O2-selective electrode (Instrumentation Lab., Milan) was coated with L-lactate oxidase as active ingredient, immobilized on a nylon net and protected by a cellulose acetate dialysis membrane, and was applied in the determination of lactate in milk in a flow injection analysis system in which the flow rate was 0.2 mL min-1, the detector cell was of ~40 µL dead volume and amperometric detection was at +0.65 V vs. a Ag - AgCl reference electrode. The carrier stream was 0.1 M phosphate buffer at pH 7.0. The calibration graph was rectilinear up to 75 µM-lactate.
Lactic acid Milk Amperometry Electrode

"Mechanized Determination Of N-octanol/water Partition Constants Using Liquid-liquid Segmented Flow Extraction"
J. Pharm. Biomed. Anal. 1994 Volume 12, Issue 12 Pages 1475-1481
Lars-Göran Danielsson* and Zhang Yu-Hui

Abstract: In the cited flow injection method, analytes (acetic acid, caffeine, p-toluidine, 2,5-dinitrophenol or alprenolol) were dissolved in water and portions (25 µL) were injected into a stream of water which was then segmented with a stream of n-octanol. After passage through an extraction coil, a portion of the aqueous phase was separated with use of a cellulose nitrate/cellulose acetate (0.45 µm) or PVDF (0.22 µm or 0.1 µm) hydrophilic membrane and analyzed spectrophotometrically. The flow injection manifold was similar to that described previously (cf., Talanta, 1994 41, 1377). Partition coefficients were calculated by varying the phase flow rates. A simplified method involving only two measurements is described. The results agreed well with literature values obtained by the shake-flask method and the RSD were 15%. Phase separation efficiencies at various flow rates are tabulated. The assay time was 15 min.
Acetic acid Caffeine 4-Toluidine 2,5-Dinitrophenol Alprenolol Spectrophotometry Sample preparation

"Amperometric Biosensors For Measurement Of Cholesterol And Application To Clinical Samples"
Ann. Chim. 1991 Volume 81, Issue 11-12 Pages 673-691
Cheillan F.; Albano A.; Mascini M.

Abstract: Cholesterol oxidase was immobilized on nylon nets and placed over the gas membrane of an oxygen probe (Oxyliquid Model 233, Idronaut, Italy) or over the cellulose acetate membrane of an H2O2 detector (Yellow Spring, USA). Both assemblies could be covered by a polycarbonate membrane to extent the linear range. The devices were tested for analysis of cholesterol by immersion in a sample solution, in a flow cell or in a flow injection system. The peroxide detector in the flow injection system proved to be the fastest and most reproducible procedure. The sensor response was linear from 0.5 to 5 mM cholesterol (I) (or up to 10 mM where the polycarbonate membrane was fitted) with a detection limit of 0.5 mM I and a coefficient of variation (n = 10) 5%. At a flow rate of 1 mL min-1, response and recovery times were 1 and 3 min, respectively, and a sampling rate of 20 h-1 was achieved. Results are presented for analysis of serum and bile samples.
Cholesterol Amperometry Sensor Clinical analysis

"Simultaneous Determination Of Hypoxanthine And Inosine With An Enzyme Sensor"
Biosensors 1986 Volume 2, Issue 4 Pages 235-244
Etsuo Watanabe, Hideaki Endo, Tetsuhito Hayashi and Kenzo Toyama

Abstract: Xanthine oxidase (I) and purine-nucleoside phosphorylase (II) were separately incorporated (details given) into cellulose triacetate membranes. To a Clark-type O electrode were applied, in order, the II-containing membrane, three sheets of unimpregnated cellulose triacetate, the I-containing membrane and a dialysis membrane. With use of apparatus similar to that described earlier (cf. J. Food Sci., 1983, 48, 496), 0.05 M phosphate buffer (pH 7.8) containing 0.1 mM cysteine was pumped to the sensor, and when the output current became steady a 50 µL portion of a solution of hypoxanthine and/or inosine was injected into the flow-line. The current decrease was recorded. Measurable responses were obtained for both analytes, with rectilinear ranges of 0.1 to 0.4 mM for hypoxanthine and 1.0 to 4.0 mM for inosine at 30°C. Storage of the sensor for 5 days at 25°C did not appreciably affect the response.
Hypoxanthine Inosine Electrode Sensor

"Complete System For Fermentation Monitoring"
Int. Biotechnol. Lab. 1986 Volume 4, Issue 2 Pages 33-40
PARKER C. P. ; GARDELL M. G. ; DI BIASIO D.

Abstract: The Control Equipment Corporation MCA-103 MultiFlow Carbohydrate Analyzer is described. It is a fully automated monitoring device based on flow injection analysis with a gas-displacement system to deliver the solvents, and has two detectors, the first of which monitors the concentration. of a specific carbohydrate or alcohol with an integral detector by using immobilized oxidase enzymes and the second of which performs a broad range of chemical analyzes by using spectrophotometric detection. Its application is illustrated by the monitoring of glucose and phosphate levels in fermentation broths. Glucose was determined in the range 0.5 to 2.0% with glucose oxidase trapped between polycarbonate and cellulose acetate membranes stretched over a platinum anode. Phosphate (10 to 100 mg l-1) was determined by mixing the eluate from the glucose detector with molybdovanadate reagent and measuring the absorbance at 400 nm.
Carbohydrates Phosphate Glucose Fermentation broth Electrode Spectrophotometry

"Curd-ripening Evaluation By Flow Injection Analysis Of L-lactic Acid With An Electrochemical Biocell During Mozzarella Cheese Manufacture"
J. Agric. Food Chem. 1996 Volume 44, Issue 10 Pages 3102-3107
Marco Esti, Maria Cristina Messia, Ennio La Notte, Pietro Lembo, Dario Compagnone, and Giuseppe Palleschi

Abstract: A flow injection analysis procedure was used for the determination of l-lactic acid during the production of mozzarella cheese. The apparatus consists of an electrochemical flow-through wall-jet cell assembled with a platinum sensor covered with the immobilized lactate oxidase enzyme and connected to an amperometer. This system was used to monitor the concentration of l-lactic acid produced by lactose fermentation catalyzed by selected starters during cheese manufacture. Lactate was detected in the range (5 x 10^-6)-(1 x 10^-4) mol/L with a detection limit of 2 x 10^-6 mol/L. l-Lactate has been measured in raw milk and during the manufacture of cow and water buffalo mozzarella cheese. The starter used was a commercially available strain of Streptococcus thermophilus. Real time analysis of lactate allowed a control of the curd-ripening evolution at different pasteurization temperatures of the milk. Values of lactic acid were compared with pH variation during the process. This method proved to be more sensitive than the pH measurement procedure for the control of the continuous production of lactic acid particularly near the "stretching point" when very slight pH variations were observed.
Lactic acid Mozzarella Amperometry Electrode

"Enzymatic Determination Of Electrophoretically Separated LDL-cholesterol From Sera Of Cardiac Patients"
J. Chem. Soc. Pak. 1995 Volume 17, Issue 1 Pages 40-42
Anwar, M.;Hashim, M.;Yaqoob, M.;Masoom, M.

Abstract: Plasma was applied to cellulose acetate membrane strips (2 µL/cm) and electrophoresis was performed in 0.05 M barbital buffer of pH 8.6 at a constant current of 0.5 mA/cm over 40 min. The strips were removed and floated on the surface of the fixation solution (5% TCA in 2.5% formaldehyde) for several seconds before soaking completely for 20 min. Staining was performed for 15 min by immersing the strips in Fat Red 7B. The LDL fraction was cut out and the cholesterol was extracted. Cholesterol was determined by an FIA system comprising an immobilized cholesterol esterase/oxidase column as previously described (cf. Atta-ur-Rahman (Ed.) 'Biochemistry for Development', 1988, p. 55).
Cholesterol Blood Plasma Blood Serum

"Determination Of Hypoxanthine In Fish Meat With An Enzyme Sensor"
J. Food Sci. 1983 Volume 48, Issue 2 Pages 496-500
ETSUO WATANABE, KAZUO ANDO, ISAO KARUBE, HIDEAKI MATSUOKA, SHUICHI SUZUKI

Abstract: The specific enzyme sensor used in this investigation was prepared by covalently immobilizing xanthine oxidase on a membrane prepared from cellulose triacetate, 4-aminomethyloctane-1,8-diamine and glutaraldehyde. This membrane was used in conjunction with an O electrode and a continuous-flow phosphate buffer system (pH 7.8). When a solution of hypoxanthine (I), or of a fish extract containing I, was injected into the flow line, the immobilized enzyme caused I to be oxidized to uric acid, with consequent decrease in the output current of the O electrode. A rectilinear calibration graph of current decrease vs. I concentration. was obtained in the range 0.06 to 1.5 mM. The sensor could be used for >100 assays without decrease of output current, and it was stable for 30 days when stored at 5°C; it was applicable in the determination of I in several types of fish, and gave results that correlated well with those obtained by a conventional enzyme method. No significant amounts of adenine, formaldehyde or acetaldehyde (any of which also reacts with the enzyme) were found in the sample solution
Hypoxanthine Marine Electrode Sensor