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
Website: @unf

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Whole Human

Classification: Biological fluid -> blood -> whole -> human

Citations 10

"Flow Multi-injection Analysis - A System For The Analysis Of Highly Concentrated Samples Without Prior Dilution"
Anal. Chim. Acta 1979 Volume 104, Issue 1 Pages 185-189
Jens Mindegaard

Abstract: The design of a medium-dispersion flow injection system for analysis of highly concentrated samples without prior dilution, is described. In this design, which can be called flow multiinjection analysis, the sample is injected in parallel with reagents into the carrier stream. For precise synchronization of injection, a multiinjector is used. For concentrated samples, the fall (or rise) of the sample injection peak is synchronized with the peak maximum of the reagent to produce a dilution proportional to the distance between the sample and reagent peaks. The method was tested by injection of Cr2O72- solutions and for determination of human albumin by the bromocresol green method.
Albumin Clinical analysis Spectrophotometry Injection technique Merging zones Gradient technique

"Determination Of Selenium By Means Of Computerized Flow Constant-current Stripping At Carbon Fiber Electrodes. Application To Human Whole Blood And Milk Powder"
Anal. Chim. Acta 1987 Volume 197, Issue 1 Pages 257-264
Chi Hua, Daniel Jagner and Lars Renman

Abstract: The main features of the flow constant-current stripping analysis for selenium(IV) are formation of a mercury film on a carbon fiber sensor in a chloride medium containing mercury(II), electrolysis in the sample at -0.20 V vs. SCE for 15-60 s, and subsequent stripping (reduction) of the mercury(II) selenide formed on the electrode surface, by means of a constant current of 0.40 µA in an acidic magnesium chloride solution containing Triton X-100. During stripping, the potential vs. time gradient is monitored at a real-time measuring rate of 25.6 kHz. All experimental parameters are under computer control. A standard addition method is used and the results are calculated and reported, both digitally and graphically. Equations relating the magnitude of the constant current to the concentration of reducible species, and, in particular, of dissolved dioxygen, are derived. Milk powder and whole blood reference samples were analyzed by high-pressure digestion in nitric acid and dilution with hydrochloric acid, in order to reduce selenium(VI) to selenium(IV), and then constant-current stripping. The results obtained by this method were lower than those obtained by the reference technique, but the values agreed within one standard deviation of the two techniques. Ions, such as iron(III) and lead(II), known to interfere with electrochemical stripping for selenium(IV) in batch analysis did not interfere in the flow approach.
Selenium Amperometry Electrode Computer

"Sensitive Flow Injection Determination Of L-lactate In Human Blood With Immobilized Enzyme Columns And Fluorimetric Detection"
Anal. Chim. Acta 1987 Volume 201, Issue 1 Pages 351-355
Kiyoshi Zaitsu, Masao Nakayama and Yosuke Ohkura

Abstract: The sample is deproteinized and the supernatant solution in 10 mM imidazole - HCl carrier solution of pH 7.0 is passed through two columns, the first packed with L-lactate oxidase and the second with horse-radish peroxidase on glass beads. The H2O2 produced in the first column is mixed with 3-(4-hydroxyphenyl)propionic acid before entry into the second column and measurement of the fluorescence at 415 nm (excitation at 320 nm). The response is rectilinear up to 500 pmol with a limit of determination of 0.5 pmol (20 µL injection). The recoveries are ~100% for 1 to 10 mM lactate with coefficient of variation (n = 10) of 1.4 and 0.97% for 0.83 and 3.9 mM, respectively.
Lactate Fluorescence Column Glass beads Immobilized enzyme

"Inductively Coupled Plasma-mass Spectrometry For Direct Multielement Analysis Of Diluted Human Blood And Serum"
J. Anal. At. Spectrom. 1997 Volume 12, Issue 9 Pages 1005-1009

Abstract: A method for the inductively coupled plasma mass spectrometry (ICP-MS) multi-element analysis of diluted human blood and serum was used for the following elements: Co, Ni, Cu, Zn, Ga, Se, Rb, Mo, Ph, Pd, Cd, Sn, Sb, W, Pt, Hg, Tl and Pb. Sample pretreatment was a simple dilution (ten times for blood and five times for serum) with a solution containing 5 g L-1 of 25% ammonia, 0.5 g L-1 Triton X-100, and 0.5 g L-1 EDTA in Millipore water. In and Sc were used as internal standards. For sample introduction a flow injection type technique (based on time instead of volume) was used. The determinations mere carried out first in a peak-jumping mode for selected masses, and then in a scanning mode. Each determination of a preparation took 75 s. The results for reference samples agreed with recommended or certified values for Co, Cu, Zn, Rb, Cd, Tl and Pb in blood, and for Rb, Mo and Cd in serum. For Ni and Hg in blood, and Cu and Zn in serum, the results agreed with one of two reference samples. The detection limits for all these elements (except for Tl) were sufficient for analysis of samples from the general population. On the other hand, the results for Se in blood, and for Co, Ni, Se, Sn and Hg in serum did not agree with recommended or certified values. No reference samples are available for Ga, Mo, Ph, Pd, Sn, Sb, W, or Pt in blood, or for Ga, Ph, Pd, W, Pt, or Pb in serum. Generally, the limits of detection for the elements in the latter group (below 0.15 µg l-1) are close to or above the levels present in the general population.
Cobalt Copper Gallium Nickel Zinc Cadmium Molybdenum Palladium pH Rubidium Selenium Antimony Lead Mercury Platinum Thallium Tin Tungsten Mass spectrometry Multielement Interferences Timed injection Reference material Triton X Surfactant

"Natural Silk Fibroin As A Support For Enzyme Immobilization"
Biotechnol. Adv. 1998 Volume 16, Issue 5-6 Pages 961-971
Yu-Qing Zhang

Abstract: A review with 40 references. Silk fibroin derived from Bombyx mori cocoon is being developed and utilized for purposes besides traditional textile material. Fibroin can be easily made up into various forms, several of which can serve as enzyme-immobilized supports. There are numerous reports on immobilized enzymes using these forms of silk fibroin as supports in which the enzyme-immobilized fibroin membranes were characterized in detail by means of spectrophotometry, IR spectra, NMR, ESR. Enzyme-immobilized fibroin membranes have been successfully used in several biosensors for the determinations of glucose, hydrogen peroxide and uric acid in which glucose and urate biosensors in a flow injection system were able rapidly to analyze various biosamples including human whole blood or serum.
Glucose Hydrogen peroxide Uric acid Sensor Review Silk fibroin membrane Immobilized enzyme

"Validation Of A Semi-automated Technique For Measuring Lactate In Whole Blood"
Clin. Chem. 1986 Volume 32, Issue 12 Pages 2175-2177
MH Weil, JA Leavy, EC Rackow, CJ Halfman and SJ Bruno

Abstract: Human and porcine heparinized blood samples were cooled in ice and 25 µL aliquots were injected into the sampling port of the Model 23L Lactate Analyzer (Yellow Springs Instrument Co., Yellow Springs, OH, USA) comprising an electrode polarographic probe with a platinum anode and a silver cathode. The membrane covering the probe consisted of two polymeric layers divided by a glutaraldehyde - cross-linked L-lactate dehydrogenase layer and the method was based on the conversion of L-lactate and oxygen to pyruvate and H2O2, requiring flavine-adenine dinucleotide as a cofactor. Results compared well with those obtained by a continuous-flow enzymatic method and the method offered precise, accurate and rapid determinations with minimal sample preparation.
Lactate Clinical analysis Electrode Polarography Enzyme Method comparison

"Evaluation Of A Miniaturized Thermal Biosensor For The Determination Of Glucose In Whole Blood"
Clin. Chim. Acta 1997 Volume 267, Issue 2 Pages 225-237
Ulrika Harborn, Bin Xie, Raghavan Venkatesh and Bengt Danielsson*

Abstract: A miniaturized thermal biosensor has been evaluated as part of a flow injection analysis system for the determination of glucose in whole blood. Glucose was determined by measuring the heat evolved when samples containing glucose passed through a small column with immobilized glucose oxidase and catalase. Samples of whole blood (1 µL) can be measured directly, without any pretreatment. The correlation in the response between the thermal biosensor, the Reflolux S meter (Boehringer Mannheim), the Granutest 100 glucose test kit (Merck Diagnostica) and the Ektachem (Kodak) instrument was evaluated. The influence of the hematocrit value and of possible interferences is reported. The correlation measurements show that the thermal biosensor calibrated with aqueous glucose standards generally gives lower values on blood glucose than the reference methods calibrated for serum or blood measurements. Mean negative biases range from 0.53 to 1.16 mmol/L. Differences in sample treatment clearly complicate comparisons and the proper choice of reference method. There was no influence from substances such as ascorbic acid (0.11 mmol/L), uric acid (0.48 mmol/L), urea (4.3 mmol/L) and acetaminophen (0.17 mmol/L) on the response to 5 mmol/L glucose. The hematocrit value does not influence the glucose determination, for hematocrit values of between 13 and 53%.
Glucose Sensor Thermistor Clinical analysis Column Immobilized enzyme Interferences Standard method

"SIRE-technology. 2. Glucose Tolerance Monitoring, After A Peroral Intake, Employing Small Volume Whole Blood Measurement With An Amperometric Biosensor"
Instrum. Sci. Technol. 1998 Volume 26, Issue 1 Pages 59-67
K. A. Johnson; D. Kriz

Abstract: A biosensor based on the flow injection of the recognition element (glucose oxidase) was applied to small volume (30 l) whole blood samples for the determination of glucose (I). The SIRE (sensors with injectable recognition elements) exhibited a linear response up to 12 mM I. The repeatability was 5.1% (n = 11) and the reproducibility (n = 4) was 8% for standard I solutions. The results obtained by the SIRE biosensor compared well with those obtained using a commercial device (Medisense, USA). Multi-analyte analysis is possible with the SIRE by simply sequentially injecting several different enzymes.
Glucose Amperometry Sensor

"An Improved Flow Injection Method For Determination Of Lactate During Exercise Studies"
Int. J. Sports Med. 1988 Volume 9, Issue 1 Pages 73-76
Y. Bergqvist, K. Hed, B. Karlberg

Abstract: An improved enzymatic fluorometric method for automated analysis of lactate in perchloric acid extracts of capillary blood with flow injection (FIA) is described. The concentrations of lactate can be measured in as little as 20 µL capillary blood from an exercising person. Within-day and between-day coefficients of variation are about 2%. The recovery of lactate from whole blood is 101%. Lactate is stable in perchloric acid extracts for at least 15 days at room temperature, and at +4°C at least 30 days. Blank fluorescence in perchloric acid extracts of blood is low with the improved method. The FIA system is simple to use, inexpensive to operate, and is recommended for any laboratory with a high throughput of samples.
Lactate Clinical analysis Fluorescence Method comparison Catalysis Enzyme

"Optimization Of Selenium Determination In Human Milk And Whole Blood By Flow Injection Hydride Atomic Absorption Spectrometry"
J. AOAC Int. 1998 Volume 81, Issue 2 Pages 457-461
Amparo Alegría, Reyes Barberá, Rosaura Farré, Emilia Ferrer, M. Jesús Lagarda, M. Angeles Torres

Abstract: A flow injection hydride atomic absorption spectrometric (FI-HAAS) method was developed for determining selenium in human milk and whole blood after microwave digestion of the sample. The sample (2 mL human milk or 0.25 mL blood) was introduced into the microwave vessel with 1.5 mL HNO3 and 0.25 mL H2O2 and 300 W (4 min) and 600 W (4 min) were applied. The digestion was completed by heating to 140°C (2-3 h). Se(VI) was reduced to Se(IV) with HCl. The instrumental conditions for FI-HAAS (concentrations of reducing agent and carrier acid, flow rate of Ar carrier gas, and sample volume injected) were optimized. The detection limit of the proposed method was 0.23 ng/mL (assay) or 115 pg Se (abs.) in biological samples (1.15 ng/mL milk, 10.4 ng/mL blood). The precision values were 5.0% for milk and 4.0% for blood. The accuracy was evaluated with two NIST reference materials. Non-Fat milk powder (found: 104.3 ± 7.2 ng/g, certified: 110 ± 10 ng/g) and whole blood seronorm (found: 81 ± 7.3 ng/mL, ref.: 83 ± 4 ng/mL). The results show the suitability of the method for Se determination in human milk and whole blood. The method was applied to whole blood samples obtained from pregnant women and to human milk.
Selenium Spectrophotometry Sample preparation Reference material Optimization