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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Human Blood

Classification: Biological fluid -> blood -> human

Citations 16

"Determination Of Selenium Balance In Healthy Children By AAS-hydride Generation And By INAA Technique"
Acta Aliment. 2002 Volume 31, Issue 3 Pages 227-234
Adányi, N., Váradi, M., Sziklai-László, I., Snyder, P., Snyder, R. D., Cser, M. Á.

Abstract: Total daily Se intake was determined by duplicate diet collection, venous blood samples were taken and urine was collected over 24 h in order to measure selenium input and output in healthy, American and Hungarian children aged 8 to 17 living in Budapest. The American children consumed not only locally processed food. Food samples were weighed, mixed, homogenised and the Se content was determined by Instrumental neutron activation analysis (INAA). The Se concentration of blood, plasma and urine samples was determined by atomic absorption spectrometry-hydride generation (AAS-HG) after wet digestion. Se intake calculated for wet weight was 62±18.5 µg/day in American children. In the Hungarian children the mean Se intake was about 35% less than in the Americans. Se concentrations in plasma were 0.84±0.16, in whole blood 1.13±0.17 µmol L-1 in the Americans, higher than those in healthy Hungarian children (0.64±0.10 and 0.83±0.12 µmol L-1, respectively) of similar age and gender. Urinary Se output calculated for creatinin was higher in the children from abroad (27.0±9.5 µg Se/day/g creatinin) compared to Hungarians (11.0±5.0 µg Se/day/g creatinin).
Selenium Spectrophotometry Volatile generation

"Indirect Potentiometric Monitoring Of Proteins With A Copper Electrode"
Anal. Chim. Acta 1985 Volume 173, Issue 1 Pages 337-341
M. L. Hitchman and F. W. M. Nyasulu

Abstract: The electrode was a 0.25-mm diameter copper wire with only the tip exposed; it was mounted in a flow-cell that incorporated a double-junction silver - AgCl reference electrode and also a platinum-wire auxiliary electrode for cathodic pre-cleaning of the copper electrode. The protein was injected (injection volume 0.2 ml) into a carrier stream (1 mL min-1) of Cu(II) in 0.05 M phosphate buffer of pH 7.0; with 10 µM-Cu(II), proteins could be determined in the concentration. range 0.1 to 1 µM, the limits of detection for human albumin, bovine albumin, ovalbumin, phosvitin, human γ-globulin and catalase being 40, 90, 100, 30, 200 and 4 µg mL-1, respectively. Chloride only interferes when present at >0.01M, as compared with >10 µM in steady-state measurements. The system has been applied to proteins eluted from a size-exclusion column.
Proteins Ovalbumins Phosvitins Enzyme, catalase Globulins Albumin SEC Electrode Potentiometry Interferences Indirect

"Photocured Polymers In Ion-selective Electrode Membranes. 6. Photopolymerized Lithium Sensitive Ion-selective Electrodes For Flow Injection Potentiometry"
Anal. Chim. Acta 1996 Volume 335, Issue 1-2 Pages 111-116
J. R. Farrell, P. J. Iles,* and T. Dimitrakopoulos

Abstract: Li ISE were prepared using the ionophore, NN-dicyclohexyl-N'N'-di-isobutyl-cis- cyclohexane-1,2-dicarboxamide (ETH 1810). A mixture of Ebecryl 600 (an aromatic epoxyacrylate), 1,6-hexanedioldiacrylate, didecylphthalate, Uvecryl P36 (a copolymerizable benzophenone photoinitiator), ETH 1810 and potassium tetrakis(p-chlorophenyl)borate was prepared and deposited on the Cu substrate of a solid contact electrode. The polymerization was carried out by exposure to a high-intensity medium pressure Hg vapor lamp for 40 min under N2. The cured electrode was conditioned in 0.1 M LiCl for 2 days. In batch-type experiments with pure LiCl solutions the electrode exhibited a hyper-Nernstian slope of 62 mV per activity decade, a log-linear range for 0.1-100 mM and a detection limit of 70 µM. The response of the electrode was independent of pH between 2 and 11 and the response time was In flow injection potentiometric experiments with 0.05 M NaCl as the carrier (1.6 ml/min) and an injection volume of 100 µl, the response slope was 49 mV per activity decade, the log-linear range was 1-100 mM, the detection limit was 0.5 mM and the sample throughput was 150/h. The FIA system was used to determine Li in lithium carbonate tablets. The selectivity of the electrode was not sufficient for the determination of Li in human blood.
Lithium Electrode Potentiometry Electrode Detector

"Glucose Determination In Blood-samples Using Flow Injection Analysis And An Amperometric Biosensor Based On Glucose-oxidase Immobilized On Hexacyanoferrate Modified Nickel Electrode"
Anal. Chim. Acta 1997 Volume 350, Issue 1-2 Pages 91-96
S. Milardovia,*, I. Kruhaka, D. Ivekovia, V. Rumenjakb, M. Tkaleca and B. S. Grabaria

Abstract: A very simple amperometric enzyme-based glucose sensor is applied as detector in flow injection analysis (FIA) of diabetic patients blood glucose. The enzyme glucose oxidase (GOD) is immobilized by a glutaraldehyde/bovine serum albumin crosslinking procedure on the surface of an alkali nickel hexacyanoferrate thin film electrocrystallized on the nickel electrode. An alkali nickel hexacyanoferrate modified nickel electrode catalyzes the reduction of the hydrogen peroxide, formed by selective biocatalytic GOD action on glucose oxidation by oxygen present in sample solutions. The developed glucose sensor has shown good sensitivity at low negative operating potentials (-300 to -100 mV vs. Ag/AgCl), sufficiently wide linear glucose concentration range (5 µM-2.9 mM), relatively long operating time (during three months of operation the initial sensitivity decreased only 30%) and no influence of the most common interferences present in human blood like proteins, ascorbic and uric acids. 38 References
Glucose Amperometry Electrode Electrode Electrode Sensor Interferences Linear dynamic range

"Sequestration Electrochemistry: The Interaction Of Chlorpromazine And Human Orosomucoid"
Anal. Biochem. 1988 Volume 171, Issue 2 Pages 290-293
D. Scott Wright, Mark L. Friedman, Sarah H. Jenkins, William R. Heineman* and H. Brian Halsall*

Abstract: A simple and rapid method is presented for determination of the association constants and stoichiometries describing ligand macromolecule interactions. Based on flow injection analysis and electrochemical detection by amperometry, the only requirements for direct measurements are that the ligand have redox properties and that these properties change upon binding to the macromolecule. Bound ligand may then be measured in the presence of free ligand. Detection limits are of the order of 2 pmol of ligand or less, a level that should provide access to previously unmeasurable systems. For the exemplary system, chlorpromazine and human orosomucoid, K0ass was determined as 0.39 x 10^6 M-1 with 0.76 chlorpromazine binding sites of this affinity per orosomucoid molecule.
Chlorpromazine Orosomucoid Amperometry Stability constants

"Testosterone Determination Using Rapid Heterogeneous Competitive-binding For Enzyme-linked Immunosorbent Assay In Flow Injection"
Anal. Lett. 1996 Volume 29, Issue 12 Pages 2125-2139
Di Benedetto, L.T.;Dimitrakopoulos, T.;Davy, R.M.;Iles, P.J.

Abstract: Heparinized blood or serum (50 µL) and 200 µL horseradish peroxidase-testosterone conjugate were incubated in polystyrene wells coated with testosterone antibody. After washing the plates with Tween 20, 200 µL H2O2/tetramethylbenzidine in acetate/citrate buffer was added and the plates re-incubated. The reaction was terminated by the addition of 50 µL 1 M H2SO4. The tetramethylbenzidine species were measured spectroscopically at 450 nm via flow injection. The ELISA kit used was a FERTIGENIX TESTO-EASIA (Medgenix Diagnostics, Australia) testosterone ELISA kit. The analysis time was reduced to 1 h compared with the conventional 150 min by reducing the antibody incubation time. The results agreed well with those obtained by an IRMA. The calibration range extended up to 12.2 ng/ml of testosterone and the assay was applied to male and female patients. The RSD was 0.5% for peak height precision.
Testosterone Immunoassay Spectrophotometry Method comparison

"Determination Of Thiamine And Its Phosphate Esters In Human And Rat Blood By High Performance Liquid Chromatography With Post-column Derivatization"
J. Chromatogr. A 1985 Volume 332, Issue 1 Pages 181-188
Mieko Kimura and Yoshinori Itokawa

Abstract: Blood, erythrocytes and plasma were deproteinized with aqueous 10% trichloroacetic acid. After centrifugation, the supernatant solution were analyzed by HPLC on a µBondapak C18 column (25 cm x 4 mm) with 0.2 M NaH2PO4 in aqueous 0.3% acetonitrile as the mobile phase (1.0 mL min-1); the eluates were subjected to post-column derivatization with 0.1% of K3Fe(CN)6 in aqueous 15% NaOH and spectrofluorimetric detection at 450 nm (excitation at 375 nm). The detection limit for thiamine and its phosphate esters was 30 fmol and recoveries were 95.0 to 100.2%. The calibration graphs were rectilinear for 50 to 200 fmol.
Thiamine Thiamine triphosphate Thiamine monophosphate HPLC Fluorescence Post-column derivatization

"Determination Of Guanine And Its Nucleosides And Nucleotides In Human Erythrocytes By High Performance Liquid Chromatography With Post-column Fluorescence Derivatization Using Phenylglyoxal Reagent"
J. Chromatogr. B 1994 Volume 654, Issue 1 Pages 19-24
Sayuri Yonekura, Masatake Iwasaki, Masaaki Kai and Yosuke Ohkura*

Abstract: Erythrocytes from 5 mL of blood were homogenized in 400 µL of water, 100 µL of 3 M HClO4 and 20 µL of 9-ethylguanine solution (200 nmol/ml; internal standard), centrifuged, the supernatant was adjusted to pH 6 with 1 M KHCO3 and passed through an ODS mini-cartridge. The first eluate (20-50 µL) was analyzed by HPLC on a column (15 cm x 4.6 mm i.d.) of TSKgel ODS-120T (5 µm) with gradient elution (1 ml/min) from 0-20% methanol in 10 mM tetra-n-propylammonium phosphate of pH 6/50 mM Na2PO4 buffer of pH 6/H2O (17:20:63 to 17:20:43) with detection at 254 nm and post-column derivatization at 80°C with 60 mM phenylglyoxal in methyl cellosolve/H2O (1:9; 0.5 ml/min) in a reaction coil (3 m x 0.5 mm i.d.) for fluorescence detection at 515 nm (excitation at 365 nm). The calibration graphs for guanine and its nucleosides and nucleotides were linear from 20-500 pmol and the detection limits were 3.2-10 pmol/20 µL. No interfering compounds were identified. The recoveries of GTP and GDP were 90-100%. No RSD are given.
Guanine Nucleosides, guanine Nucleotides, guanine HPLC Fluorescence Interferences Post-column derivatization

"Continuous Measurement Of Cations In The Bloodstream Of Patients"
Anaesthesist 1981 Volume 30, Issue 6 Pages 290-292
Dennhardt, R.;Konder, H.;Schindler, J.G.

Abstract: An electrochemical flow-through system is described which allows continuous determination of Na+, K+, and Ca2+ concentrations in the blood stream. The ion-selective electrodes show excellent selectivity constants. Activity potentials of >97% of theoretical measurement characteristics of the electrodes (Nernst factor) were achieved. Results of patient measurements are demonstrated. (SFS)
Sodium Potassium Calcium Electrode Electrode Electrode

"Flow Injection Immunoenzyme Assay Of Human IgG Using The Reaction Of Enhanced Chemiluminescence"
Biotekhnologiya 1989 Volume 5, Issue 4 Pages 525-531
Aref'ev A.A.; Vlasenko S.B.; Gavrilova E.M.; Egorov A.M.; Osipov A.P.

Abstract: A rapid method human IgG immunoenzyme determination based on the 'sandwich'-scheme of antigene concentration analysis is described. Both stages of this method are automated by using the techniques of flow injection analysis that are carried out in a kinetic regime. Antigene- antibody interaction kinetics were studied. The temporal ranges and concentrations of the employed reagents were determined. This allows to reduce the time of antigene-antibody interaction stages to 2-3 min. The proposed flow injection immunoenzyme method of human IgG assay with a chemiluminescence peroxidase detection system has a lower level of IgG determination 10^-8-10-9M. The total time of analysis is 5-10 min.
Immunoglobulin G Chemiluminescence Immunoassay Kinetic

"Robust, Reliable Biosensor For Continuous Monitoring Of Urea During Dialysis"
Clin. Chem. 1996 Volume 42, Issue 7 Pages 1079-1085
L Della Ciana and G Caputo

Abstract: We developed a new urea sensor for the online monitoring of hemodialysis adequacy. The biosensor consisted of an immobilized urease cartridge placed between magneto-inductive conductivity cells. The biosensor output was taken as the conductivity difference between these cells. The device was placed on the ultrafiltrate line of a paired filtration dialysis system. The amount of urease present in the cartridge was sufficient for the complete conversion to ammonium carbonate of urea up to 35 mmol/L. Agreement was good between the urea concentration by the biosensor method and an automated analyzer for seven patients: range 8.07-30.3 mmol/L (22.6-84.8 mg/dL blood urea nitrogen, BUN); intercept 0.20±0.1 mmol/L (0.55±0.4 mg/dL, BUN); slope 1.01±0.01; r 0.997; S-y/x 0.40 mmol/L (1.11 mg/dL BUN). The device proposed meets the requirements of accuracy, cost, ruggedness, and ease of use (no calibration required) for a biosensor to be used for continuous monitoring of hemodialysis.
Enzyme, urease Urea Electrode Sensor Clinical analysis Dialysis Immobilized enzyme Method comparison Process monitoring

"Determination Of Glucose In Blood By Flow Injection Chemiluminescent Analysis"
Fenxi Ceshi Tongbao 1987 Volume 6, Issue 6 Pages 11-15
Li Jianzhong Zhang Zhujun

Abstract: The determination of glucose in human blood by flowing injection chemiluminescent analysis by enzymatic reaction of glucose-glucose oxidase, the generated H2O2 reacts with luminol producing chemiluminescence. The optimum conditions is discussed. The method is sensitive, selective and has a wide linear range. The detection limit is 0.1 µg/ml. The chemiluminescent peak hight is linear with the concentration of glucose from 0 to 600 µg/dl or more. Relative standard deviation is 4%.
Glucose Chemiluminescence Clinical analysis

"Determination Of Zinc In Serum, Blood, And Ultrafiltrate Fluid From Patients On Haemofiltration By Graphite-furnace - Atomic Absorption Spectroscopy Or Flow Injection Analysis - Atomic Absorption Spectroscopy"
J. AOAC Int. 1994 Volume 77, Issue 3 Pages 722-727
Jimenez De Blas, O.;Seisdedos Rodriguez, R.;Hernandez Mendez, J.;Sanchez Tomero, J.A.;De Leon Gomez, B.;Vicente Gonzalez, S.

Abstract: Two methods were optimized for the determination of zinc in samples of blood, serum, and ultrafiltrate fluid from patients with chronic renal impairment undergoing hemofiltration. In the first procedure, after acid digestion of the samples, Zn in blood and serum is determined by a system coupled to flow injection analysis and atomic absorption spectroscopy. The method is rapid, automated, simple, needs small amounts of sample, and has acceptable analytical characteristics. The analytical characteristics obtained were as follows: determination range of method, 0.05-2.0 ppm of Zn; precision as coefficient of variation (CV), 5.3%; recovery, 95-105%; and detection limit (DL), 0.02 ppm. The second method is optimized for ultrafiltrate fluid because the sensitivity of the first procedure is not suitable for the levels of Zn (ppb or ng/mL) in these samples. The technique chosen was atomic absorption spectroscopy with electrothermal atomization in a graphite furnace. The analytical characteristics obtained were as follows: determination range of method, 0.3-2.0 ppb Zn; CV, 5.7%; recovery, 93-107%; and DL, 0.12 ppb. The methods were used to determine zinc in samples of blood, serum, and ultrafiltrate fluid from 5 patients with chronic renal impairment undergoing hemofiltration to discover whether there were significant differences in the zinc contents of blood, serum, and ultrafiltrate fluid after the hemofiltration process. An analysis of variance of the experimental data obtained from a randomly selected group of 5 patients showed that zinc concentrations in the ultrafiltrate fluid, venous blood, and venous serum do not vary during hemofiltration (p < 0.05), whereas in arterial blood and serum, the time factor has a significant effect. Blood (5 g) was digested with 4 mL of 65% HNO3 and 1 mL of 96% H2SO4 at 130-150°C for ~1 h. After cooling, the solution was heated with 2 mL of 65% HNO3 and 1 mL of 65% HClO4. The mixture was again cooled, treated dropwise with 1 mL of 30% H2O2 and re-heated to 180°C. The residue (2 ml) was made up to 10 mL with water. The sample was diluted 1:5 with water after acid digestion. Serum was treated similarly except that H2O2 was not used and the volumes of acid were: 3 mL of 65% HNO3 and 1 mL of 96% H2SO4 in the first addition, and 1 mL of 65% HNO3 in the second. The samples were not further diluted. For analysis of ultrafiltrate, the dilution was 1:95. Sample was then mixed with water with an air intake to ensure nebulization. Analysis was by electrothermal AAS (operating conditions tabulated) with an acetylene-air flame and measurement at 213.9 nm. A graphite-furnace AAS method was optimized for the ultrafiltrate (details given). Calibration ranges were 0.05-2 and 0.3-2 ppb of Zn in blood and serum, and ultrafiltrate, respectively with corresponding detection limit of 0.02 and 12 ppb. Corresponding recoveries and RSD were 93-105 and 93-107%, and 5.3 and 5.7%.
Zinc Spectrophotometry Sample preparation Sensitivity Optimization

"Computer Acquisition And Analysis Of Data In Enzymic Fluorimetric Continuous-flow Methods For The Measurement Of Glucose, Lactate, Pyruvate, Alanine, Glycerol And 3-hydroxybutyrate In Human Blood"
J. Autom. Methods Manag. Chem. 1986 Volume 8, Issue 2 Pages 49-55
CLIVE S. HETHERINGTON, MICHAEL KEIR, RAYMOND STAPPENBECK, ALISTAIR SIMM, LINDSAY L. BRIGHAM, ANDREW W. SKILLEN, and ALAN W. HODSON

Abstract: The continuous-flow methods for the cited analytes were performed as described previously [Lloyd et al., Clin. Chem.(Winston-Salem, N.C.) 1978, 24, 1724] with minor modifications to reagent concentration, which are listed. The computer program for data acquisition was written in BASIC for the Apple II microcomputer. Correlation between results obtained manually and by the computer method was very good (r >0.95 except that for pyruvate, which was 0.8834).
Alanine 3-hydroxybutyrate Glucose Glycerol Lactate Fluorescence Computer Enzyme

"Post-column Derivatization In Narrow-bore Capillaries For The Analysis Of Amino-acids And Proteins By Capillary Electrophoresis With Fluorescence Detection"
J. Microcolumn Sep. 1994 Volume 6, Issue 4 Pages 373-384
S. Douglass Gilman, Jeremy J. Pietron, Andrew G. Ewing

Abstract: A post-column reactor was fabricated with a 4-160 µm gap between two 10 µm i.d. capillaries and a reservoir over the gap (details and schematic diagram given). The reservoir was filled with derivatization solution comprising 9 mM o-phthaldialdehyde, 10 mM 2-mercaptoethanol and 3% methanol in 25 or 100 mM borate of pH 9.5. The reactor was used in a home-made capillary electrophoresis instrument previously described (Wallingford and Ewing, Anal. Chem., 1987, 59, 1762) with laser-induced fluorescence and UV detection. The use of the reactor was exemplified by the separation of eight amino-acids on a column (100 cm x 10 µm i.d.; 80 cm to the gap and 82.5 cm to the detection window) with a separation buffer to 25 mM borate of pH 9.5, a separation potential of 30 kV and laser-induced fluorescence detection. The system was used for the detection of amino-acids and proteins with mass detection limits of 130 and 5.2 amol for glycine and human transferrin, respectively.
Amino Acids Proteins Spectrophotometry Electrophoresis Fluorescence Post-column derivatization

"Multisyringe Flow Injection Analysis Of Stable And Radioactive Yttrium In Water And Biological Samples"
Anal. Chim. Acta 2005 Volume 539, Issue 1-2 Pages 189-194
Y. Fajardo, E. G&oacute;mez, F. Garcias, V. Cerd&agrave; and M. Casas

Abstract: A novel multisyringe flow injection (MSFIA) method for the determination of stable and radioactive yttrium by means of a liquid-liquid extraction has been developed. An on-line column containing di-2-ethylhexylphosphoric acid (HDEHP) - a highly selective extractant for the analyte - adsorbed on a C18 support is employed to carry out the isolation from the matrix. Stable and radioactive yttrium concentrations are determined by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and by a low background proportional counter, respectively. The proposed method shows important advantages because the manual handling of radioactive samples is avoided and throughput is increased. Moreover, as the extractant can be reused, cost per analysis and waste generation are reduced. The lower limit of detection (LLD) of stable yttrium is 10 µg l-;1, whereas for 90Y is 0.05 Bq. The automated isolation process yields a yttrium recovery close to 100% with a relative standard deviation of 2.3% (n = 10). Our methodology has been successfully applied to different spiked water and biological samples.
Yttrium Spectrophotometry Scintillation counter Radiochemical Speciation Multisyringe Extraction C18 Column