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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Classification: Biological tissue -> liver

Citations 10

"Determination Of Zinc And Cadmium In Small Amounts Of Biological Tissues By Microwave-assisted Digestion And Flow Injection Atomic Absorption Spectrometry"
Anal. Chim. Acta 1988 Volume 214, Issue 1-2 Pages 421-427
M. Burguera and J. L. Burguera, O. M. Alarcón

Abstract: A system comprising a microwave oven, a peristaltic pump, a closed flow system and an AAS instrument is described and illustrated. Samples of liver or kidney were prepared in a final volume of 10 mL of 10 M HNO3, and then digested in the oven at ~200 W for 8 min. The digest was aspirated into a collector tube, pumped to a flowing sample collector, and finally injected into the carrier stream (H2O). Zinc and Cd were determined by flame AAS in an air - acetylene flame at 213.9 and 228.8 nm, respectively. Recoveries of 20 to 60 µg of Zn and of 5 to 10 µg of Cd were 97 to 103 and 96 to 98%, respectively. The coefficient of variation (n = 5) were 2 to 5% and 3 to 6% for Zn and Cd, respectively, and results for two reference materials agreed with expected values.
Zinc Cadmium Sample preparation Spectrophotometry Reference material

"Selective Determination Of Antimony(III) And Antimony(V) In Liver Tissue By Microwave-assisted Mineralization And Hydride Generation Atomic Absorption Spectrometry"
Fresenius J. Anal. Chem. 1995 Volume 353, Issue 2 Pages 133-136
C. Rondón, J. L. Burguera, M. Burguera, M. R. Brunetto, M. Gallignani and Y. Petit de Peña

Abstract: Antimony(III) and antimony(V) species have been selectively determined in liver tissues by optimizing the acidic conditions for the evolution of stibine using the reduction with sodium borohydride. The results show that a response for Sb(III) of 0.5 to 20 g l-1 was selectively obtained from samples in a 1 mol l-1 acetic acid medium. The best response for total antimony from 1 to 20 g l-1 is obtained after sample treatment with a 0.5 mol l-1 sulfuric acid and 10% w/v potassium iodide. Microwave digestion has been necessary to release quantitatively antimony species from sample slurries. The amount of Sb(V) was calculated from the difference between the value for total antimony and Sb(III) concentrations. A relative standard deviation from 2.9 to 3.1% and a detection limit of 0.15 and 0.10 g l-1 for Sb(III) and total Sb has been obtained. The average accuracy exceeded 95% in all cases comparing the results obtained from recovery studies, electrothermal atomic absorption spectrometry and the analysis of certified reference materials.
Antimony(3+) Antimony(5+) Sample preparation Spectrophotometry Speciation Volatile generation Volatile generation

"Determination Of Tin In Biological Samples Using Gaseous Hydride Generation - Inductively Coupled Plasma Atomic Emission Spectrometry"
Anal. Biochem. 1990 Volume 190, Issue 1 Pages 71-77
Katsuhiko Yokoi, Mieko Kimura and Yoshinori Itokawa

Abstract: Liver, brain, testis or kidney was homogenized and heated with HNO3 and HClO4 in Kjeldahl flasks until white fumes appeared. Water was added with heating until the solution was clear and colorless. An aliquot of the solution was treated with trichloroacetic acid (I) and diluted with water to 0.2% in I. This solution was mixed, in a continuous-flow hydride-generation system (diagram given), with 1% I solution and then with 0.5% NaBH4 in 0.1% NaOH solution and passed through a gas - liquid separator (design presented) and the hydride, in an Ar-stream, was determined by ICP-AES at 189.989 nm. The limit of detection was 30 pg mL-1 of Sn, mean recovery was 87 to 99% and the coefficient of variation was 1.2%.
Tin Spectrophotometry Dilution Phase separator Detection limit Volatile generation Volatile generation Kjeldahl

"Inductively Coupled Plasma Atomic Emission Spectrometric Determination Of Copper By Suction-flow Online Liquid -liquid Extraction Of Its Macrocyclic Dioxotetramine Chelate"
Bull. Chem. Soc. Jpn. 1987 Volume 60, Issue 5 Pages 1930-1932
Takahiro Kumamaru,Yoko Nitta,Hiroshi Matsuo and Eiichi Kimura

Abstract: Sample solution, containing ~30 g mL-1 of Ni(II), was placed in a PTFE suction cup and mixed with 5 mM 6-hexadecyl-1,4,8,11-tetra-azacyclotetradecane-5,7-dione and 1 M borate buffer (pH 9). The solution was pumped to a segmentor containing CHCl3 and the segmented solution was carried to an extraction coil and a phase separator. The organic extract was pumped into the nebulizer of the ICP spectrometer and Cu(II) was determined at 324.754 nm. Response was rectilinear for up to 500 ng mL-1 of Cu(II) and the detection limit was 1.5 ng mL-1. The coefficient of variation (n = 10) was 2.2%. Aluminium, Cr(III) and Fe(III) interfered. The method was applied to determine Cu(II) in biological tissues, and results agreed well with those obtained by graphite-furnace AAS.
Copper Spectrophotometry Sample preparation Chelation Extraction

"Online Column Preconcentration And Determination Of Trace Elements By Flow Injection Inductively Coupled Plasma - Atomic-emission Spectrometry"
Fenxi Huaxue 1993 Volume 21, Issue 12 Pages 1410-1413
Peng, X.J.;Jiang, Z.C.;Zeng, Y.N.

Abstract: Sample solution was treated with 13.4 µM-meso-tetrakis-(4-sulfophenyl)porphyrin and ammoniacal buffer of pH 9.24 before dilution with water and heating at 100°C for 30 min. The mixture was applied at 1 ml/min to a column of silica gel (10-40 µm) and elution was effected with 2 M HCl. The eluate was sprayed directly into the spectrograph for ICP-AES analysis for Cu, Mn, Ni, Fe, Pd and Cd. The detection limits for these elements were 0.32-26.8 ng/ml and the RSD (n = 6) were 1.3-3%. No interference was observed from co-existing ions. The enrichment factor was 9.3-11.3 and the sampling rate was 12 runs/h. The method was employed in analysis of bovine liver and tomato leaves reference materials.
Copper Manganese Nickel Iron Palladium Cadmium Spectrophotometry Preconcentration Reference material Silica gel Column Interferences

"Determination Of Organomercury And Mercury In Environmental Samples By Flow Injection Atomic Fluorescence Spectrophotometry"
Int. J. Environ. Anal. Chem. 1996 Volume 63, Issue 3 Pages 187-193
S. C. Edwardst; C. L. Macleod; W. T. Corns; T. P. Williams; J. N. Lester

Abstract: Environmental samples (dogfish and liver certified reference materials, eel and roach) were digested by heating for 4 h at 60°C with 20% tetramethylammonium chloride in a closed vessel. The digest was extracted with toluene, centrifuged, and the extract was mixed with 1 mL 1 mM cysteine or -thiosulfate. The aqueous phase was analyzed for organomercury by flow injection AFS. Total Hg was determined after microwave digestion of samples with 30% H2O2/HNO3/H2O. Sample (100 µL) was injected into a stream of water which was mixed with a stream (0.4 ml/min) of 25 g/l potassium peroxodisulfate and 1.2 g/l CuSO4 in 0.25 M H2SO4 for oxidation to Hg2+ in a 0.5 mL reaction coil. The flow then merged with a stream (0.5 ml/min) of 100 g/l SnCl2 in HCl for reduction to Hg(O) in a 1 mL reaction coil. The Hg(O) was carried in Ar (after separation in a gas liquid separator) to a hygroscopic tubular membrane for drying and to the AFS instrument. The calibration graph was linear for 5-1000 µg/l methylmercury ions and the detection limit was 2 µg/l. The RSD (n = 10) at 25 µg/l was 3.7%. The calibration graph for inorganic Hg was linear for 0.05-1000 µg/l and the detection limit was 0.02 µg/l. Extraction efficiences were 70-80%.
Mercury Methylmercury ion Fluorescence Sample preparation Sample preparation Reference material Extraction Phase separator Speciation

"Selective Determination Of Inorganic Mercury And Methylmercury In Tissues By Continuous-flow And Cold Vapor Atomic Absorption Spectrometry"
J. Anal. Toxicol. 1993 Volume 17, Issue 2 Pages 87-92
Raja H. Atallah and David A. Kalman

Abstract: A method has been developed for the determination of inorganic (InHg) and methylmercury (MeHg) in solubilized tissues with continuous-flow (flow injection) cold vapor atomic absorption spectrometry. Kidney, liver, and brain tissues were spiked with MeHg and InHg and solubilized at an elevated temperature in a solution containing 90 g/L NaOH, 2 g/L L-cysteine, and 4 g/L NaCl. Total mercury determination was achieved by continuous-flow cold vapor atomic absorption spectrometry using an inlet system containing a flow-through photo-oxidation reactor and sodium borohydride as the mercury reductant. InHg was selectively determined in the presence of MeHg with this method when using stannous chloride as the reductant. MeHg concentrations were computed as the difference between the values obtained from the two analyzes. Recoveries for spiked tissues were above 95% for InHg and MeHg. Quantitation limits for InHg and total mercury in tissues were 0.4 and 0.6µg/g, respectively. MeHg chloride levels from kidney tissues of exposed rats were evaluated using the present method in comparison with another method in which MeHg was measured using solvent extraction and capillary gas chromatography with electron capture detection. Kidney, liver and brain tissues (0.25 g) were spiked with methylmercury (I) or Hg (5 and 10 µg) and solubilized at 60°C in a solution containing 10 g L-1 of NaCl (4 ml), 10 g L-1 of L-cysteine (2 ml) and 450 g L-1 of NaOH (2 ml). For Hg determination, tissue (100 µL) was injected at 1.8 mL min-1 and treated with SnCl2 at 0.8 mL min-1 with a stream of N at 350 mL min-1. Total Hg was determined with use of a photo-oxidation modification step to convert I to Hg; sample was acidified with a stream of 6 M HCl containing K persulfate at 0.8 mL min-1 which provided online acidification of the solubilized solution before entering the photoreactor and reacting with NaBH4. Determination limits for inorganic Hg and total Hg were 0.4 and 0.6 µg g-1 in tissues, respectively. Recoveries were >95% for Hg and I by continuous-flow- and cold vapor-AAS.
Methylmercury ion Mercury Spectrophotometry Speciation Photochemistry Phase separator

"Determination Of Semduramicin Sodium In Poultry Liver By Liquid Chromatography With Vanillin Post-column Derivatization"
J. AOAC Int. 1994 Volume 77, Issue 3 Pages 577-582
Ericson, J.F.;Calcagni, A.;Lynch, M.J.

Abstract: Semduramicin sodium (I) was extracted from homogenized liver with 1% NH4OH in methanol/H2O (4:1) for 3 min at 55°C and centrifuged. After sonication and mixing, the sample was applied to a C8 Bond Elut cartridge (details given) and washed with water and aqueous 75% methanol; elution was with ethyl acetate. The eluate was dried and the residue was reconstituted in CH2Cl2/iso-octane (1:1) and sonicated for 5 min. The resulting solution was applied to a silica BondElut cartridge and washed with CH2Cl2/iso-octane (1:1) followed by ethyl acetate. Elution was effected with CH2Cl2/methanol (9:1). The eluate was dried and the residue was reconstituted in ethyl acetate/iso-octane (2:3). After mixing and sonicating for 2 min, the solution was injected on to a column (25 cm x 4.6 mm i.d.) of Zorbax silica, equipped with a guard column (2 cm), with ethyl acetate/iso-octane/anhydrous acetic acid/triethylamine/methanol (650:350:4:2:1) as mobile phase (0.6 ml/min) and post-column derivatization with vanillin (0.3 ml/min) with detection at 522 nm. The calibration graph was linear from 32-320 ng/g of I and the detection limit was 25 ng/g. The recovery was 95% for 40-320 ng/g and the RSD was 10%.
Semduramicin sodium LC Spectrophotometry Post-column derivatization

"Catalytic Determination Of Cobalt In Liver By Flow Injection Spectrophotometry"
J. Braz. Chem. Soc. 1991 Volume 2, Issue 1 Pages 47-50
M.A.Z. Arruda, E.A.G. Zagatto, A.O. Jacintho and S.M.B. Brienza

Abstract: A flow-injection procedure is proposed for the catalytic spectrophotometric determination of cobalt in liver. The method exploits the catalysis of this metal on Tiron oxidation by hydrogen peroxide in alkaline medium. Influence of pH, reagent concentrations, temperature, ionic strength, flow rates, feasibility of kinetic discrimination and presence of potential interfering ions were studied. With a sampling rate of about 40 samples per hour, the system yields precise results (RSD usually < 1% within the 0.20 - 2.00 pg Co I-I range) in agreement with graphite furnace atomic absorption spectrometry. The detection limit is 2 ng Co L-1 and the consumption of Tiron is only 0.13 mg per sample. Additional procedures for selectivity enhancement are suggested.
Cobalt Spectrophotometry Catalysis

"Screening Method For The Quantitative Determination Of 12 Sulfonamides In Meat, Liver And Kidney By HPLC And Online Post-column Derivatization"
Mitt. Geb. Lebensmittelunters. Hyg. 1993 Volume 84, Issue 2 Pages 263-273
Guggisberg, D.;Mooser, A.E.;Koch, H.

Abstract: Meat samples were homogenized, extracted with acetone and following hydrolysis and neutralization of the aqueous phase, sulfonamides were extracted with ethyl acetate and purified on a silica gel column. Sulfabenzamide was added as internal standard and the sulfonamides were separated by reversed-phase HPLC on a Spherisorb ODS column with acetonitrile - acetate buffer mobile phase at 1.0 mL min-1. Post-column derivatization [diazotization and reaction with N-(1-naphthyl)ethylenediamine dihydrochloride] permitted highly specific detection by visible spectrophotometry at 550 nm. The detection limit was 2 ppb of sulfonamides.
Sulfonamides Sample preparation HPLC Spectrophotometry Post-column derivatization