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 -> kidney

Citations 7

"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

"Use Of Focused Microwaves For Expeditive Shortening Of Sample Pre-treatment: Digestion And Reduction Procedures Prior To Selenium Speciation As Selenium(IV) Or Selenium(VI)"
Analyst 1995 Volume 120, Issue 8 Pages 2171-2174
W. Bryce, A. Izquierdo and M. D. Luque de Castro

Abstract: Methods for sample digestion and reduction of Se(VI) to Se(IV) using a focused microwave digestor, prior to Se determination, are described. The sample digestion method consisted of a three-step microwave digestion programme, using HNO3 and H2O2 (details given). The reduction of Se(VI) to Se(IV) was carried out online in a flow injection manifold in a 1 m Teflon reactor placed in the microwave chamber, using 6 M HCl as reductant. After reduction, the sample stream was diluted online before Se(IV) determination by flow injection cathodic stripping voltammetry (details given). The methods were applied to various sample types, viz., milk, sausage, kidney and water, and reduced the time required for both sample digestion and Se(VI) reduction.
Selenium(VI) Selenium(IV) Sample preparation Voltammetry Heated reaction Microwave Speciation

"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

"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 Twelve Sulfonamides In Meat And Kidney By HPLC And Post-column Derivatization"
Mitt. Geb. Lebensmittelunters. Hyg. 1991 Volume 82, Issue 1 Pages 45-55
Pacciarelli, B.;Reber, S.;Douglas, C.;Dietrich, S.;Etter, R.

Abstract: Homogenized meat and kidney samples (10 g) were extracted with CH2Cl2 - acetone (1:1), the extract was centrifuged, the solution was filtered and the filtrate was acidified with acetic acid. A portion (0.5 ml) of the solution was cleaned up on a cation-exchange cartridge of Chromabond SA (500 mg) and the sulfonamides were eluted with methanol. The eluate was evaporated to dryness, the residue was dissolved in 0.5 mL of solvent A (5.5% CH3CN in buffer solution of pH 5) and a portion (5 µL) of the solution was analyzed by HPLC on a column (12.5 cm x 4 mm) of 5 µm LiChrospher 100 RP-18 with gradient elution (0.8 mL min-1) with solvent B [CH2CN - ethanol - buffer solution of pH 5 (5:1:4)] in solvent A. After UV detection at 270 nm, the column effluent was treated with fluorescamine reagent (0.3 mL min-1) and detected at 495 nm (excitation at 395 nm). The detection limits ranged from 0.5 to 5 ppb. Recovery of 50 ppb of all of the sulfonamides added ranged from 70 to 90%, except for sulfaguanidine (32%) and sulfamethizole in kidney (38%).
Sulfonamides HPLC Fluorescence Spectrophotometry Sample preparation Buffer Extraction Post-column derivatization PPB

"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