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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Biological material

Classification: Biological material

Citations 28

"Determination Of The Substrates Of Dehydrogenases In Biological Material In Flow Injection Systems With Electrocatalytic NADH Oxidation"
Anal. Chim. Acta 1984 Volume 163, Issue 1 Pages 299-303
A. Schelter-Graf, H. -L. Schmidt and H. Huck

Abstract: Applications are described of the NADH-sensitive system described previously (Huck et al., Anal. Abstr., 1984, 46, 8J126) that incorporated epoxyacrylic resin-bound dehydrogenases and a modified graphite electrode. The determination of D- and L-lactate in butter, L-glutamate in beef cubes, and ethanol in beer, and the control of the enzymatic hydrolysis of N-acetyl-DL-leucine by aminoacylase are discussed. The results obtained agreed well with those by spectrophotometric methods.
Ethanol l-Glutamate d-Lactate l-Lactate N-Acetyl-DL-leucine Electrode Potentiometry Method comparison Reactor Enzyme

"Determination Of Nickel And Cobalt In Natural Waters And Biological Material By Reductive Chronopotentiometric Stripping Analysis In A Flow System Without Sample Deoxygenation"
Anal. Chim. Acta 1985 Volume 175, Issue 1 Pages 79-88
H. Eskilsson and C. Haraldsson, D. Jagner

Abstract: Samples (100 ml) of natural waters, or portions (0.5 to 5 ml) of acid digests of seawater sediments or bovine liver, were mixed with 3 M NH3 - HCl buffer (pH 9.2) and 0.1 M dimethylglyoxime(I) solution in ethanol; Co(III) species formed during acid digestion were reduced with NaBH4. Electroanalysis was performed in a thin-layer flow cell with a vitreous-carbon working electrode. The microprocessor-controlled operational sequence included(I) plating of a mercury film on to the carbon electrode;(II) potentiostatic adsorption (at -0.5 V vs. the SCE) of the Ni(II) - and Co(II) - I complexes on to the mercury film; (iii) constant-current reduction of the metal ions in a 5 M CaCl2 medium and simultaneous recording of the working-electrode potential vs. time; (iv) chemical removal of the mercury film; and (v) cleaning of the vitreous-carbon surface. To determine Co in presence of a large excess of Ni, an adsorption potential of -0.75 V vs. the SCE was used. Detection limits (after 70 s of adsorption) were 8.6 ng L-1 for Ni(II) and 10.5 ng L-1 for Co(II).
Nickel Cobalt Potentiometric stripping analysis Electrode Sample preparation Interferences

"Flow Injection Analysis For Traces Of Zinc With Immobilized Carbonic Anhydrase"
Anal. Chim. Acta 1985 Volume 178, Issue 2 Pages 209-215
Kunio Kashiwabara, Toshiyuki Hobo, Eigo Kobayashi and Shigetaka Suzuki

Abstract: Bovine carbonate dehydratase was immobilized on CNBr-activated Sepharose 4B and packed in a small glass column. The metal ions were removed from the enzymes easily by passing 0.01 M pyridine-2,6-dicarboxylic acid through the column at 1.0 mL min-1. The activity increase after passing a Zn sample solution through the column was measured by injecting 0.1 M 4-nitrophenyl acetate in dimethyl sulfoxide into the Tris buffer stream and measuring at 400 nm the 4-nitrophenol formed. The increase in peak area was proportional to the amount of Zn in the sample. A rectilinear calibration graph was obtained for 10 to 400 ng of Zn. The coefficient of variation for 0.13 µg of Zn was 4.9%. The method was successfully applied to the determination of Zn in tea, sediment and spring water. The immobilized enzyme can be used repeatedly and Zn can be concentrated on the column, permitting very low concentration. to be determined.
Zinc Spectrophotometry Immobilized enzyme Preconcentration

"Flow Injection Potentiometric Stripping Analysis-a New Concept For Fast Trace Determinations"
Anal. Chim. Acta 1986 Volume 179, Issue 1 Pages 389-398
Wolfgang Frenzel and Peter Brätter

Abstract: The system described by Schulze and Frenzel (Mikrochim. Acta, 1984, I, 191) was used with four different flow-through cells. The carrier solution contained various amounts of Hg and the vitreous carbon was pre-coated with Hg. Up to four elements could be determined simultaneously at ppb to % levels. Rectilinear response was obtained for Pb and Cd in the range 5 to 100 µg l-1. The method was sucessfully applied to the determination of Zn, Pb and Cu in tap-water at levels down to 20 µg L-1 with 0.5 mL samples and to the direct determination of Pb and Cd in acid digests of biological samples.
Metals, heavy Zinc Lead Copper Cadmium Electrode Potentiometric stripping analysis Sample preparation Tecator

"Reductive Stripping Chronopotentiometry For Selenium In Biological Materials With A Flow System"
Anal. Chim. Acta 1987 Volume 198, Issue 1 Pages 231-237
H. Eskilsson and C. Haraldsson

Abstract: Reductive stripping chronopotentiometry in a flow system is used for determination of selenium in mussels and NBS bovine liver after acid digestion. The automated flow system contains a thin-layer cell with a mercury film electrode. In the deposition step, mercury(II) selenide is formed on the mercury film surface; the stripping step involves reduction to mercury and hydrogen selenide. This reduction is done in a separate solution of almost saturated calcium chloride, which eliminates interferences from oxygen so that solutions need not be deoxygenated. The detection limit is 0.14 µg L-1 selenium at a deposition time of 120 s.
Selenium Potentiometry

"Selective Stopped-flow Determination Of Manganese With Luminol In The Absence Of Hydrogen Peroxide"
Anal. Chim. Acta 1995 Volume 302, Issue 2-3 Pages 275-282
Abaji Gaikwad, Manuel Silva and Dolores Pérez-Bendito*

Abstract: A novel stopped-flow chemiluminescence method for the determination of manganese by reaction with luminol in the presence of high concentrations of sodium chloride and the absence of hydrogen peroxide is proposed. Light emission takes place over a very short interval (less than ~200 ms). The activity of other ions that react with luminol under the experimental conditions used in the absence of hydrogen peroxide is examined. The proposed method permits the sensitive determination of manganese (detection limit 1.8 x 10^-8 M), with high precision (RSD < 1%), selectivity (thanks to the presence of triethanolamine) and sample throughput (100 samples h-1). It was applied to the determination of manganese in certified biological samples. A possible mechanism for the sodium chloride effect was proposed.
Manganese Chemiluminescence Stopped-flow Selectivity

"Polyurethane Foam As A Sorbent For Continuous-flow Analysis: Preconcentration And Spectrophotometric Determination Of Zinc In Biological Materials"
Anal. Chim. Acta 1998 Volume 366, Issue 1-3 Pages 263-269
Djane Santiago de Jesus, Ricardo Jorgensen Cassella, S&eacute;rgio Luis Costa Ferreira, Antonio Celso Spinolla Costa, Marcelo Souza de Carvalhod and Ricardo Erthal Santelli*

Abstract: A simple and accurate procedure was developed to pre-concentrate and determine zinc in biological matrices. A polyurethane foam (PUF) minicolumn was used for the first time for on-line pre-concentration. This system was applied to pre-concentrate zinc from aqueous solutions which is sorbed as zinc-thiocyanate complex. Then, the complex was eluted by water and zinc was determined by spectrophotometry using 4-(2-pyridylazo)-resorcinol. The method was validated by the analysis of several biological certified reference materials. The detection limit was 0.9 ng mL-1 and the RSD was 1.2% for 1 min pre-concentration time. Generally, concentration of Fe(III), Al(III), Mo(VI), Ni(II), Mn(II), Cu(II), and Co(II) found in biological matrices did not interfere. Dynamic ranges of concentration from 20 to 100 ng mL-1 (1 min pre-concentration time) and from 5 to 20 ng mL-1 (5 min pre-concentration time) achieve a sample throughput of 20 and 8 samples per hour and a pre-concentration factor of 8 and 32, respectively.
Zinc Spectrophotometry Preconcentration Polyurethane foam

"Lead Preconcentration Onto C-18 Minicolumn In Continuous-flow And Its Determination In Biological And Vegetable Samples By Flame Atomic Absorption Spectrometry"
Talanta 1996 Volume 43, Issue 6 Pages 977-983
Rosimar Lima, Katia Christina Leandro and Ricardo Erthal Santelli*

Abstract: Biological and vegetable materials were wet ashed with acid treatment. The sample stream (4 ml/min) in acetic acid buffer of pH 4.6 was merged with a reagent stream (0.27 ml/min) of diethylammonium NN-diethyldithiocarbamate and passed through a reaction coil (200 cm). The lead/diethyldithiocarbamate complex formed was retained on a C-18 minicolumn (3 cm x 2 mm i.d.). At the same time IBMK flowed to a loop (380 µL) and a carrier stream (3 ml/min) of water passed to the AAS instrument. The commutator switched and a small volume of water washed the minicolumn. The column was eluted with IBMK from the loop and the eluate was analyzed by AAS at 217 nm using an air/acetylene flame. Calibration graphs were linear for 20-100 µg/l of Pb with a detection limit of 3 µg/l. The RSD (n = 3) was 3.8% for 25 µg/l Pb. Sample throughput was 24 samples/h.
Lead Spectrophotometry Sample preparation Preconcentration MIBK

"Determination Of Arsenic, Chromium, Selenium And Vanadium In Biological Samples By Inductively Coupled Plasma Mass Spectrometry Using Online Elimination Of Interference And Preconcentration By Flow Injection"
J. Anal. At. Spectrom. 1994 Volume 9, Issue 5 Pages 611-614
Les Ebdon, Andrew S. Fisher and Paul J. Worsfold

Abstract: A 0.5 g portion of the biological material was digested with 3 mL of HNO3 and 2 mL of water for 16 h and then irradiated in a microwave oven at 300 W for 3 min. After cooling, 0.1 g of potassium persulfate was added and the digest was microwaved at 300 W for a further 2 min; H2O2 (1 ml) was then added and the digest was irradiated with a 150 W Xe lamp for 18 h to decompose arsenobentaine. The digest was diluted to 50 mL with Tris buffer (pH 9) following the addition of 3 mL of 60% NaOH. A 200 µL portion of this solution was injected into the water carrier stream (1.5 ml/min) of the flow manifold and passed through the alumina column (2.5 cm x 3 mm i.d.). The analytes were subsequently eluted from the column by injecting 200 µL of 1 M HNO3 into the carrier stream and determined by ICP-MS. The detection limits for V, Cr and As were 0.12, 0.6 and 0.9 µg/g. To achieve a detection limit of 1 µg/g for Se it was necessary to use an alternative procedure which involved the pre-concentration of 10 mL of digest. The recoveries of 60 ng/ml of Cr, Se and V and 600 ng/ml of As from a spiked biological reference material (Tort-1, lobster hepatopancreas) were 98-109%, respectively.
Arsenic Chromium Selenium Vanadium Mass spectrometry Reference material Preconcentration Interferences

"Online Separation And Sequential Determination Of Trace Amounts Of Heavy Metals In Biological Materials By Flow Injection Inductively Coupled Plasma Atomic-emission Spectrometry"
J. Anal. At. Spectrom. 1996 Volume 11, Issue 2 Pages 107-110
M. T. Siles Cordero, E. I. Vereda Alonso, A. Garc&iacute; de Torres and J. M. Cano Pav&oacute;n

Abstract: Certified biological reference materials were mineralized by reacting with 65% HNO3, heating under reflux until the cessation of nitrous fumes, adding 35% H2O2 and concentrating to remove HNO3. The mixture was neutralized with NaOH, adjusted to pH 3.6 with glycine/HCl buffer and 1 M NaClO4 was added. The resulting solution was mixed, at a T-shaped solvent segmentor in a FIA system, with a carrier solution of 1,5-bis(di-2-pyridyl)methylene thiocarbohydrazide in DMF/IBMK (1:1) and passed through an extractor coil (200 cm x 0.8 mm i.d.). The resulting solution was split at a phase separator and the organic phase filled the injection loop of the ICP-AES instrument. The sample was pushed into the cross-flow nebulizer by an IBMK/DMF (1:1) carrier solution and the emission signals were recorded (plasma type not given). Calibration graphs were linear for 10^-2000 ng/ml for Co and Cu and 20 to 2000 ng/ml for Zn and Cd with detection limits of 4.8, 1.1, 20.3 and 23 ng/ml, respectively. The corresponding RSD (n = 8) were 1.9, 1.2, 2.8 and 3.7%. The effects of foreign ions are discussed with S2- being the most serious interferent.
Cobalt Copper Zinc Cadmium Spectrophotometry Interferences Reference material MIBK Phase separator

"Determination Of Copper, Cadmium And Lead In Biological Samples By Isotope-dilution Inductively Coupled Plasma Mass Spectrometry After Online Pretreatment By Anodic-stripping Voltammetry"
J. Anal. At. Spectrom. 1996 Volume 11, Issue 5 Pages 353-357
Tarn-Jiun Hwang and Shiuh-Jen Jiang

Abstract: Standard reference materials plus appropriate amounts of the corresponding enriched isotope solutions were digested with HNO3/H2O2 in a closed vessel by heating in a microwave oven. The digest was diluted with 0.1 M NH4NO3 as supporting electrolyte and a 2 mL portion was injected from a PTFE sample loop into the carrier stream (1.2 ml/min) of the supporting electrolyte in an FIA system. The stream was pumped through an anodic-stripping voltammetry flow cell constructed from a PTFE rod (details given) and equipped with a reticulated vitreous-carbon working electrode, an Ag/AgCl reference electrode and a Pt-wire counter electrode. A deposition potential of -1.2 V was applied to the working electrode for a preselected period, after which the carrier flow was stopped. The working electrode potential was changed to +0.2 V and 10 mM HNO3 (2 ml/min) was passed through the flow cell to elute the analytes for determination by isotope-dilution ICP-MS (operating conditions given). The effects of the sample and eluent flow rates and the presence of matrices were investigated. The detection limits for Cu, Cd and Pb were 70, 10 and 70 pg/ml, respectively. Calibration graphs were linear up to at least 200 ng/ml.
Cadmium Copper Lead Mass spectrometry Reference material Electrochemical stripping Interferences

"Simultaneous Determination Of Silicon And Phosphorus In Biological Standard Materials With Online-column Flow Injection Spectrophotometry"
Fresenius J. Anal. Chem. 1988 Volume 332, Issue 2 Pages 162-166
Yoshio Narusawa, Tsutomu Katsura and Fuki Kato

Abstract: Biological standard material (1 g), viz, NIES chlorella or pepperbush or NBS bovine liver, was ashed, the ash was fused with Li2CO3 - H3BO3 for 15 min at ~1000°C, and the cooled melt was dissolved in and diluted to 100 mL with 1 M HCl. A 2.5 mL portion of extract was diluted with water (2.5 ml) and the mixture was cleaned up by cation exchange on a column (3 cm x 8 mm) of Dowex 50W-X8 (100 to 200 mesh) pre-conditioned with 2 M HCl (10 ml) and water (2 x 10 ml). Elution was effected with 0.5 M HCl (5 x 2 ml), the combined eluates were evaporated to dryness, 0.5 mL of 0.25 M Na2CO3 was added and, after evaporation to dryness, the residue was fused at ~1000°C for 15 min. The melt was dissolved in water containing 0.01 M EDTA (1 ml) and the solution was diluted to 25 mL with water. Phosphorus and Si were then determined by flow injection analysis as previously described (Anal. Abstr., 1988, 50, 8B123) with online anion-exchange separation on a column (15 cm x 4.6 mm) of TSK-gel SAX (5 µm). Most commonly occuring ions, e.g., Ca and Mg, were removed on the cation-exchange column; however, arsenate and germanate were not. Results agreed with those by ICP-AES.
Silicon Phosphorus Ion exchange Spectrophotometry Merging zones Method comparison Simultaneous analysis Reference material

"Determination Of Zinc By Flow Injection With Fluorimetric Detection In A Micellar Medium"
Fresenius J. Anal. Chem. 1996 Volume 355, Issue 1 Pages 88-91
N. Ga&ntilde;&aacute;n Guti&eacute;rrez, F. S&aacute;nchez Rojas and J. M. Cano Pav&oacute;n

Abstract: Sample was injected into a carrier stream (1.9 ml/min) of 0.02 M acetate buffer of pH 5, the carrier stream merged with a 3% Triton X-100 stream (1.9 ml/min) and the solutions were mixed in a mixing coil (150 cm x 0.5 mm i.d.). The resulting stream merged with a reagent stream (1.2 ml/min) of 5 mM salicylaldehyde thiocarbohydrazone in DMF, passed through a mixing coil (200 cm x 0.5 mm i.d.) and the fluorescent intensity was monitored at 462 nm (excitation at 410 nm). Calibration graphs were linear for 10^-1000 ng/ml of Zn with a detection limit of 5 ng/ml and a RSD (n = 10) of 1.8 and 2% for 50 ng/ml and 100 ng/ml Zn, respectively. The effects of foreign ions are discussed. The method was applied to the determination of Zn in drinking water and biological materials.
Zinc Fluorescence Triton X Micelle Surfactant

"Determination Of Inorganic Phosphate By The Use Of Immobilized Enzymes In A FIA System"
Anal. Lett. 1994 Volume 27, Issue 2 Pages 309-321
Mori, H.;Kogure, M.;Kawamata, S.;Nagamoto, A.;Yamamoto, H.

Abstract: Inorganic phosphate was determined after conversion into NADPH by passage in a carrier solution (0.4 ml/min) of Tris buffer of pH 8 containing 0.1 M sucrose, 3 mM MgCl2, 1 mM NADP+ and 50 µM-glucose 1,6-diphosphate through a 8 cm reaction column at 30°C containing 40 iu each of sucrose phosphorylase, phosphoglucomutase and glucose-6-phosphate dehydrogenase bonded via glutaraldehyde to aminopropyl-bonded glass beads. A 12 µL flow cell was used for fluorimetric detection at 460 nm (excitation at 340 nm). The calibration graph was linear from 0.2 µM to 0.1 mM phosphate with a detection limit of 0.1 µM-phosphate and RSD of 4.1% at 10 µM (n = 5). For test determination of P in calf thymus this method gave the same value (5%) as the established molybdenum blue method.
Phosphate Fluorescence Glass beads Immobilized enzyme

"Flow Injection Determinations Of Creatine And Creatinine Using Packed Bed Enzyme Reactors Under Equilibrium Conditions"
Anal. Lett. 1994 Volume 27, Issue 3 Pages 495-510
Moges, G.;Johansson, G.

Abstract: Plexiglas tube reactors were included in series in a flow injection system for determination of creatinine (I) and creatine (II). The tubes contained immobilized enzymes on CPG-10 controlled-pore glass pre-silanized with aminopropylsilane and activated with glutaraldehyde. The immobilized enzymes were creatinine amidohydrolase (E.C. 3.5.2.10.) in reactor A for determination of I and creatine kinase (E.C. 2.7.3.2), pyruvate kinase (E.C. 2.7.1.40.) and lactate dehydrogenase (E.C. 1.1.1.27.) in reactor B for determination of II, pyruvate and ADP. The flow stream buffer contained 13 mM magnesium acetate, 13 mM potassium acetate, 1.1 mM ATP, 1 mM phosphenol pyruvate and 0.25 mM NADH in 70 mM imidazole acetate of pH 7.8 and detection was at 340 nm. Reactor A was bypassed if only II was determined. Linear calibration graphs were obtained for 5-400 µM-I and -II with detection limits of 6.4 µM-I and 3 µM-II. The RSD was 0.7% for 100 µM of both I and II. Reactor working lives were >5 months for A and 3 months for B.
Creatine Creatinine Spectrophotometry Controlled pore glass

"Online Precipitation/dissolution System For The Preconcentration And Determination Of Manganese Traces By Atomic Absorption Spectrometry"
Spectrochim. Acta B 1996 Volume 51, Issue 14 Pages 1935-1941
Carola Dittfurth, Evaristo Ballesteros, Mercedes Gallego and Miguel Valc&aacute;rcel*

Abstract: Sample solution (8 or 24 ml; pH 3), containing 40-720 ng of Mn, was injected into a carrier stream of 0.5% H2O2 (at 4 ml/min) and merged with a reagent stream of ammoniacal buffer solution of pH 9 (4 ml/min). The combined streams were heated at 40°C, and the resulting hydrated Mn(IV) oxide was collected on a stainless-steel filter (3 cm2; pore size 0.5 µm). The Mn collected on the filter was dissolved by a stream of 2 M HNO3 (1 ml/min) and carried to a fuel-lean air-acetylene flame. Enrichment factors of up to 55 were obtained. For 8 and 24 mL samples the calibration graphs of peak heights were linear for 5-90 and 1.3-30 ng/ml of Mn and the detection limits were 2 and 1 ng/ml, respectively. Results for digests of biological reference materials agreed with the certified values.
Manganese Sample preparation Spectrophotometry Reference material Preconcentration Precipitation Heated reaction

"A Comparative Study Of Methods For Determining Selenium In Biological Materials"
Acta Cient. Venez. 1990 Volume 41, Issue 1 Pages 5-10
Burguera, J.L.;Burguera, M.;Gallignani, M.;Alarcon, O.M.

Abstract: A comparative study of the analytical performance of fluorimetric spectrophotometric, atomic absorption spectrometric, flow injection analysis with atomic absorption spectrometric, flow injection analysis with atomic absorption spectrometric detection, hydride generation with atomic absorption spectrometric detection and hydride generation with molecular emission cavity analysis detection methods has been carried out for the determination of selenium in biological materials. Based on results concerning detection limit, linearity and sensitivity, only the fluorimetric and hydride generation with atomic absorption spectrometric detection methods were suitable for the determination of selenium in biological materials. Whereas, the spectrophotometric, flame absorption spectrometric flow injection atomic absorption spectrometric and hydride generation with molecular emission cavity detection, due to its worse detection limits and poorer sensitivities, were found to be unsuitable for the determination of selenium in such matrices. The accuracy of the fluorimetric and hydride generation with atomic absorption spectrometric detection methods were tested by using NBS standard reference materials.
Selenium Spectrophotometry Fluorescence Spectrophotometry Spectrophotometry Detection limit Sensitivity Reference material Method comparison

"Determination Of A Small Amount Of A Biological Constituent By The Use Of Chemiluminescence. 14. The Flow Injection Analysis Of Protein Using Ultrasonic Chemiluminescence Of Luminol"
Bull. Chem. Soc. Jpn. 1988 Volume 61, Issue 8 Pages 2996-2998
Tadashi Hara,Kazuhiro Nakatsu,Akihiro Arai,Tatsunari Yoshida and Kazuhiko Tsukagoshi

Abstract: Proteins were determined by means of the ultrasonically induced chemiluminescence of luminol with Co(II) as catalyst; the flow injection system is described (with diagram). Optimum reagent concentration. were 50 µM-luminol, 0.1 M NaOH, 5 nM-Co(II) and 1 mM hexadecyltrimethylammonium bromide. Calibration graphs were rectilinear from 5 µg L-1 to 0.1 g L-1 of bovine serum albumin, bovine serum γ-globulin, human serum albumin and human serum γ-globulin; the detection limit was 200 pg for each protein. The coefficient of variation was 2.9% (n = 8) at 10 mg L-1 of bovine serum albumin. The sampling rate was 60 h-1. (For Part XIII see preceding abstract).
Proteins Chemiluminescence Clinical analysis Catalysis Indirect Optimization Ultrasound

"Use Of A Flow Injection Sample Manipulator As An Interface Between A High-Performance Liquid Chromatograph And An Atomic Absorption Spectrophotometer"
Clin. Chem. 1981 Volume 27, Issue 9 Pages 1546-1550
BW Renoe, CE Shideler and J Savory

Abstract: We describe an integrated, molecular-absorbance, atomic absorption instrument for studying metal/ligand binding in clinical samples. For an interface between the 'high performance' liquid chromatograph and the atomic absorption instrument we used a flow injection sample manipulator, thus allowing both the chromatograph and the atomic absorption detector to operate at their separate optimum conditions. After specimen separation with a gel permeation column, we measured the molecular components of the column eluate by molecular absorbance spectrometry and the atomic components (calcium and magnesium) by flame atomic absorption spectrophotometry. This instrument system is capable of separating and analyzing multiple components within 20 min of injection of the sample on the column. The chromatograms presented demonstrate the utility of the system for investigating metal binding to a variety of ligands in clinical samples.
Calcium Magnesium Clinical analysis Spectrophotometry HPLC Complexation Injector Interface

"Studies On The FIA-ICP-AES Method. 3. Simultaneous Determination Of Calcium, Sodium, Magnesium, Aluminum, Iron, Copper, Chromium, Manganese And Zinc In Biological And Clinical Samples"
Huanjing Huaxue 1989 Volume 8, Issue 1 Pages 68-73
Chen, Hao; Kong, Lingying; Jiang, Zucheng; Zen, Yune; Cheng, Zhujun; Hu, Hongxing

Abstract: A method has been developed for the determination of Ca, Na, Mg, Al, Fe, Cu, Cr, Mn, and Zn in biological and clinical samples by using the FIA-ICP-AES technique. Several factors including volume of sample introduced, exposure time, and ICP operating conditions influencing the analysis were investigated. Under optimum experimental conditions, the detection limits for the analytes were 0.032-6.5 mg/mL, the relative standard deviations are in the range 0.58-2.8% (n = 10), and the recoveries of the method are higher than 90%. The results obtained show that the FIA-ICP-AES technique is superior to the method of continuous nebulization ICP-AES in analysis efficiency, precision, matrix effect, and introducing the amount of sample. This method has been applied to the analysis of a variety of biological and clinical samples.
Calcium Sodium Magnesium Aluminum Iron Copper Chromium Manganese Zinc Spectrophotometry Clinical analysis Optimization Method comparison

"Cold Vapor Generation For Inductively Coupled Argon Plasma Atomic-emission Spectrometric Analysis. 3. Mercury"
J. AOAC Int. 1994 Volume 77, Issue 2 Pages 473-480
Anderson, K.A.;Isaacs, B.;Tracy, M.L.;Moller, G.

Abstract: Sample was digested with concentrated HNO3 and K2CrO4 for 6-12 h at room temperature and then for 24 h at 95°C, and the digest was treated with enough saturated KMnO4 solution to surpass the endpoint, which is recognized when the solution remains a clear purple or a brown precipitate remains after mixing. The mixture was heated at 70-95°C for 10 min then treated dropwise with saturated oxalic acid solution until it became clear and colorless or, for soils the samples changed from dark brown to milky white, and vortex-mixed. The resulting solution was mixed with 10 M HCl and 6% NaBH4 in 5% NaOH in a continuous-flow manifold (diagram given) and subjected to ICP-AES with measurement at 194.232 nm. The instrumental detection limit was 0.2 µg/l. The method was used to analyze biological materials and environmental materials, including plants, soil and water (which was analyzed directly). Recoveries were 68.4-97.0%.
Mercury(II) Sample preparation Spectrophotometry

"Pre- And Post-column Derivatization Chemistry In Conjunction With HPLC For Pharmaceutical Analysis"
J. Chromatogr. Sci. 1988 Volume 26, Issue 8 Pages 362-371
Danielson, N.D.;Targove, M.A.;Miller, B.E.

Abstract: A review is presented, with 248 references, which covers derivatization - HPLC analysis of, e.g., alkaloids, amines, antibiotics, barbiturates and steroids. Application to biological materials is included.
Alkaloids Amines Antibiotics Barbiturates Steroids HPLC Review Post-column derivatization

"Microwave Oven Digestion Procedures And Flow Injection For The Analysis Of Biological Samples"
J. Flow Injection Anal. 1988 Volume 5, Issue 2 Pages 121-131
M. DE LA GUARDIA and A. SALVADOR, J.L. BURGUERA* and M. BURGUERA

Abstract: A review is presented, with 41 references, of the fundamentals of microwave-oven digestion, of modifications necessary for laboratory use, and of applications of the method, particularly in flow injection analysis. The fundamentals of the use of microwave ovens for sample decomposition, the modifications proposed to adapt the commercially available microwave ovens to the laboratory work requirements and the possibilities and applications of those methods in flow injection analysis are discussed
Clinical analysis Sample preparation Sample preparation Review Closed loop Dilution Extraction

"Chemi-bioluminescent Flow Injection Analysis"
J. Flow Injection Anal. 1989 Volume 6, Issue 1 Pages 1-2
Akio Tsuji

Abstract: A brief review is presented of the development of chemi-bioluminescent flow injection analysis and its applications, especially in the determination of steroids and cholic acid in biological materials.
Steroids Cholic acid Bioluminescence Chemiluminescence Review

"Flow Injection Determination Of Cyanide With Use Of An Immobilized Enzyme"
J. Flow Injection Anal. 1996 Volume 13, Issue 2 Pages 138-147
Deguchi, T.;Fukaura, K.;Norimatsu, S.;Minami, S.;Tanaka, A.;Sanemasa, I.

Abstract: Rhodanese was immobilized on 200-400 mesh aminopropyl-controlled pore glass beads (particle size 585 angstrom and surface area 45.1 m2/g) by the action of glutaraldehyde in Tris buffer of pH 8.6. Sample (100 µL) was injected into a stream of 10 mM Tris buffer of pH 8.6 at 0.7 ml/min and merged with a stream of 5 mM Na2S2O3 at 0.3 ml/min before entering the immobilized enzyme reactor (4 cm x 2 mm i.d.) at 0°C. The generated thiocyanate ion was mixed with a reagent stream of 5 mM Fe(III) in a reaction coil (2 m x 0.5 mm i.d.) and detection was at 460 nm. The calibration graph was linear from 0-1 mM cyanide, with a detection limit of 15 µM. When determining 0.5 mM cyanide, the RSD was 2.3%. Only ascorbate interfered. The immobilized rhodanese was stable for at least 10 h when used continuously. The sampling frequency was 20/h. The method was applied to the analysis of environmental and clinical samples.
Cyanide Spectrophotometry Interferences Controlled pore glass Immobilized enzyme

"Application Of Flow Injection Analysis In Trace Element Determination Of Body Fluids"
J. Trace Elem. Electrolytes Health Dis. 1993 Volume 7, Issue 1 Pages 9-18
Burguera JL, Burguera M

Abstract: The principle of flow injections analysis (FIA) is briefly described, along with some of its advantages for analytical measurements. A review of the development, current status and application of FIA coupled with optical or electrochemical techniques for the determination of various elements in body fluids is presented. Further, the analytical potential of FIA for the determination of elements in biological materials is then summarized and trends in the methodology are given brief consideration.
Trace elements Electrochemical analysis Spectrophotometry Review

"Progress Of The Study On The Photometric Analysis Of Ascorbic Acid"
Lihua Jianyan, Huaxue Fence 1996 Volume 32, Issue 4 Pages 239-241
Zhang, W.D.;Wang, J.B.

Abstract: A review is presented, covering literature published between 1990-1995, of determination of ascorbic acid in foods, biological materials and drugs by e.g., conventional photometry, flow injection absorptiophotometry and catalytic-kinetic photometry. (27 references).
Ascorbic acid Spectrophotometry Review Optosensing

"Computerized Methods In Electroanalytical Chemistry"
J. Anal. Chem. 1988 Volume 43, Issue 3 Pages 541-554
Gratzl, M.;Pungor, E.

Abstract: A review is presented, with 35 references, of computerized methods for carrying out noise treatment, feature selection and pattern recognition in electrochemical analysis. Problems discussed include noise in turbulent voltammetric cells, acceleration of measurement with ion-selective electrodes (ISE), evaluation of potentiometric and amperometric flow-through titration curves, automated evaluation of polarograms and potentiometric flow injection peaks, automated calibration of ISE and automation of the potentiometric in vivo analysis of biological materials.
Amperometry Electrode Electrode Potentiometry Computer Review Signal noise