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 -> pig

Citations 8

"Determination Of Cadmium In Foodstuffs And Plant Materials By Flow Injection Spectrophotometry Including Ion Exchange"
Anal. Chim. Acta 1995 Volume 306, Issue 2-3 Pages 343-349
JoséA. Gomes Neto, H. Bergamin Filho, Raquel P. Sartini and Elias Ayres G. Zagatto*

Abstract: Dried powdered food or plant material (1 g) was digested with 10 mL of HNO3 for 30 min at 50°C; 2 mL of 30% H2O2 was added and the mixture evaporated to near dryness at 110°C. The residue was dissolved in 10 mL of 0.1 M HNO3 and diluted to 25 mL with water for FIA. The sample stream (3.8 ml/min) merged with an acidic NaCl stream (1.2 ml/min) then the flow passed through a strongly basic AG1 X-8 BioRad column (1 cm x 5 mm i.d.) and the Cd chlorocomplexes were retained. The flow-through the column was reversed and the analyte was eluted with 2 M NaNO3/0.1 M HNO3 (2.9 ml/min). The flow was merged with 75 µg Cd in 0.25 M ammonium acetate solution (1.2 ml/min) and then a second reagent stream which had been formed by merging 0.5 mM Malachite green and 2 M KI in 0.5% ascorbic acid (both at 0.5 ml/min); detection was at 690 nm. The detection limit was 0.11 µg/l Cd; RSD for sample digests containing 19.7 and 5.12 µg/l Cd were 2.26% and 2.72%, respectively (n = 12). The method was validated by analyzing standard reference materials (rice flour, pig kidney, dried copepoda) containing 0.75-2.71 µg/g Cd (results given). A second anion-exchange column was added to the FIA system to enable the analysis of samples which had been mineralized with HNO3/perchloric acid.
Cadmium Ion exchange Spectrophotometry Biorad Reference material

"Flow Injection Anodic-stripping Voltammetry At A Gold Electrode For Selenium(IV) Determination"
Anal. Chim. Acta 1995 Volume 308, Issue 1-3 Pages 96-101
D. W. Bryce, A. Izquierdo and M. D. Luque De Castro*

Abstract: The Se(IV) sample solution in 0.3 M Na2SO4 was passed through a Chelex-100 column to remove interfering divalent cations. A 600 µL volume of the column eluate was injected into a 0.3 M Na2SO4 carrier stream which was subsequently merged with a 1.5 M H2SO4 stream. The resulting flow (0.2 ml/min) was passed through the voltammetric cell. A deposition potential of -0.4 V was applied to the working Au electrode vs. Ag/AgCl (3 M KCl) reference electrode, Au auxiliary electrode) for 9 min. The flow was stopped and after 15 s a potential scan from -0.4 to 1.16 V was carried out at 40 mV/s with a pulse amplitude of 50 mV. The calibration graph for Se(IV) had two linear sections, from 5-30 ng/ml and 40-100 ng/ml. The RSD (n = 11) for the determination of 20 ng/ml Se(IV) was 2.3%. The recovery of 40-60 ng/ml Se(IV) and 10^-20 ng/ml Se(VI) (after reduction) from spiked water was >97%. The method was validated by analyzing a lyophilized pig kidney certified reference material containing 10.3 µg/g selenium.
Selenium(IV) Electrode Voltammetry Chelex Interferences Reference material Stopped-flow

"Determination Of Ochratoxin A In Pig's Kidney Using Enzymic Digestion, Dialysis And High Performance Liquid Chromatography With Post-column Derivatization"
Analyst 1979 Volume 104, Issue 1245 Pages 1171-1175
D. C. Hunt, Lesley A. Philip and N. T. Crosby

Abstract: A method for the determination of ochratoxin A in pig's kidneys is described. The detection limit is less than 1 µg kg-1. By using enzymatic digestion concurrently with dialysis and by controlling the pH conditions, the sample is extracted and interfering co-extracts removed without the use of column chromatography. The final determination employs reversed-phase high-performance liquid chromatography with either a phthalimidopropylsilane or a C22(docosyl) bonded column, and the sensitivity of the fluorescence detector is increased ten-fold by the formation of a post-column derivative with ammonia solution.
Ochratoxin A HPLC Sample preparation Post-column derivatization Dialysis

"Fullerene: A Sensitive And Selective Sorbent For The Continuous Preconcentration And Atomic Absorption Determination Of Cadmium"
J. Anal. At. Spectrom. 1997 Volume 12, Issue 4 Pages 453-457
Yaneira Petit de Peña, Mercedes Gallego, Miguel Valácrcel

Abstract: The use is described, with diagrams of the flow injection manifold used, of a column of 80 mg of fullerene C60 for the separation and pre-concentration of Cd as its pyrrolidine-1-carbodithioate complex. The sample solution (6 ml) of 3-300 ng of Cd2+ in 0.1 M HNO3 is injected into a stream (0.3 ml/min) of 0.1% ammonium pyrrolidine-1-carbodithioate solution in aqueous 5% ethanol, and the resulting complex is adsorbed on the fullerene, from which it is subsequently eluted with 0.2 mL of IBMK for online flame AAS. This combination of fullerene and chelating agent is superior to other continuous-flow separation/pre-concentration systems. Other heavy metals are tolerated in 600-1000-fold concentrations with respect to Cd; also, the results for Cd in standard reference oyster tissue, porcine kidney and bovine liver showed that there is negligible interference from the decomposition products of these samples.
Cadmium Sample preparation Spectrophotometry Sample preparation Preconcentration MIBK Reference material Interferences Extraction

"Online Preconcentration And Determination Of Mercury In Biological Samples By Flow Injection Vapor Generation Inductively Coupled Plasma Atomic-emission Spectrometry"
Fresenius J. Anal. Chem. 1995 Volume 352, Issue 6 Pages 615-617
Pedro Cañada Rudner, José Manuel Cano Pavón, Amparo García de Torres and Fuensanta Sánchez Rojas

Abstract: Hair was digested with 65% nitric acid for 30 min followed by microwave digestion at 360 W for 4 min and 180 W for 10 min. After cooling for 14 min, the digests were concentrated by evaporation, neutralized with NaOH and diluted with water. Pig kidney and dogfish muscle were prepared by the method of Niazi et al. (Analyst, 1993, 118, 821). The extracts (1.4 ml/min) were mixed with 0.2 M HCl/0.2 M glycine buffer of pH 3.6 (0.4 ml/min) in a FIA system. The flow merged with a stream of 1,5-bis(di-2-pyridyl)methylene thiocarbonohydrazide in IBMK (0.5 ml/min) at a solvent segmentor. The stream passed through an extraction coil (200 cm x 0.5 mm i.d.) to a membrane phase separator and the aqueous phase went to waste. The organic phase filled a sample loop (500 mL volume) and the excess went to waste. The sample was injected into a carrier stream (3.3 ml/min) of IBMF/DMF (1:1) and merged with a reagent stream (0.5 ml/min) of SnCl2 in DMF. The resulting stream passed through a mixing coil (100 cm x 0.8 mm i.d.) for the generation of Hg vapor. The gas and solvent passed to a gas-liquid separator and to Hg vapor was swept to a ICP torch by Ar. The Hg was determined by ICP-AES (operating details tabulated). The calibration graph was linear for 10^-2500 ng/ml of Hg(II) with a detection limit of 4 ng/ml and RSD (n = 10) of 1% at 100 ng/ml. The effects of foreign ions are discussed.
Mercury Sample preparation Spectrophotometry Sample preparation Extraction Preconcentration Interferences Phase separator Volatile generation MIBK Volatile generation

"Determination Of Residues Of Carbadox And Some Of Its Metabolites In Swine Tissues By High Performance Liquid Chromatography Using Online Pre-column Enrichment And Post-column Derivatization With UV - Visible Detection"
J. Chromatogr. A 1988 Volume 456, Issue 1 Pages 105-119
M. M. L. Aerts*, W. M. J. Beek and H. J. Keukens, U. A. Th. Brinkman

Abstract: Homogenized muscle, liver or kidney was extracted with methanol - acetonitrile (1:1) and the extract was cleaned up on a column (40 cm x 10 mm) of alumina - Florisil. The percolate was evaporated under N, the residue was dissolved in water and the solution was extracted with 2,2,4-trimethylpentane. Portions (2 ml) of the aqueous phase were injected into a column-switching HPLC system comprising an analytical column (20 cm x 3 mm) of ChromSpher C18 (5 µm) with a guard column (1 cm x 2.1 mm) and a preliminary enrichment column (6 cm x 4.6 mm), both of Bondapak C18/Corasil (37 to 50 µm). The mobile phase was acetonitrile - 0.01 M Na acetate buffer of pH 6 (3:17). Post-column derivatization with 0.5 M NaOH was studied. Flow rates (ml min-1) were 0.6 (eluent), 0.5 (sample enrichment) and 0.23 (derivatization reagent). Detection was at 420 nm. Limits of determination were 1 to 5 µg kg-1, recoveries were 81 to 87% and the coefficient of variation was 4 to 10% (n = 8 to 10).
Carbadox HPLC Spectrophotometry Post-column derivatization

"Analysis Of 6R- And 6S-tetrahydrobiopterin And Other Pterins By Reversed-phase Ion-pair Liquid Chromatography With Fluorimetric Detection By Post-column Sodium Nitrate Oxidation"
J. Chromatogr. B 1993 Volume 617, Issue 2 Pages 249-255
Yoshihiro Tani* and Tomochika Ohno

Abstract: A mixture of D-neopterin, biopterin, pterin, 7,8-dihydropterin, 6R-L-erythro-5,6,7,8-tetrahydrobiopterin and 6S-L-erythro-5,6,7,8-tetrahydrobiopterin was analyzed by HPLC at 40°C on a column (25 cm x 4.6 mm) of Cosmosil 5C18 equipped with a guard column (5 cm x 4.6 mm) of the same packing. Elution (1 ml/min) was effected with 0.1 M phosphate buffer of pH 3 containing 5% methanol, 3 mM sodium octylsulfate, 0.1 mM Na2EDTA and 0.1 mM ascorbic acid. Post-column derivatization was achieved by mixing the eluate with a stream of 5 mM NaNO2 (1 ml/min) before passing through a reaction coil (no dimensions given) at 80°C; fluorescent detection was performed at 440 nm (excitation at 350 nm). The calibration graphs were linear from 0.02-5 ng of each compound injected, with detection limits of 10^-20 pg. Recoveries from tissues ranged from 84.7-99.6% and the within-assay RSD were 0.7-3.7%. The method was applied to the analysis of homogenates of rat liver, kidney and 6 regions of the brain.
d-Neopterin Biopterin Pterin 7,8-Dihydropterin 6R-L-erythro-5,6,7,8-tetrahydrobiopterin 6S-l-erythro-5,6,7,8-tetrahydrobiopterin Fluorescence HPLC Post-column derivatization Heated reaction

"Determination Of Ionophores In The Tissues Of Food Animals By Liquid Chromatography"
Food Addit. Contam. 1995 Volume 12, Issue 6 Pages 731-737
Gerhardt G, Salisbury CD, Campbell HM

Abstract: A liquid chromatographic method for determining residues of ionophores in bovine, porcine, and avian tissues is described. Tissues were extracted with iso-octane-ethyl acetate and the extracts purified on silica solid-phase extraction columns. Monensin, narasin and salinomycin were detected by UV absorbance following post-column derivatization with vanillin, and lasalocid was detected underivatized using fluorescence. In muscle, kidney and fat, all drugs were determined from a single sample extract. In liver, a separate extraction was done to determine lasalocid. The detection limit for lasalocid, narasin and salinomycin was 5 ppb; for monensin it was 2 ppb. Average recoveries were: lasalocid-71.0%; monensin-94.3%; salinomycin-97.2%; narasin-94.1%.
Lasalocid Monensin Narasin Salinomycin HPLC Fluorescence Post-column derivatization