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 -> pig

Citations 4

"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

"Determination Of Total Phosphorus In Biological Samples By Flow Injection Analysis With Spectrophotometric Detection"
Bull. Chem. Soc. Jpn. 1993 Volume 66, Issue 3 Pages 966-968
Edison Munaf, Wenzhi Hu and Hiroki Haraguchi

Abstract: Sample (8 to 40 g) was digested using 40 mL of 1 M HClO4, shaken vigorously and centrifuged at 3000 rpm for 5 min. A 20 mL portion of the supernatant solution was adjusted to pH 6.5 with 1.5 M potassium hydrogen carbonate and a 20 µL portion of this solution was injected into a carrier stream which merged with a stream (100 µL min-1) of 4% potassium peroxodisulfate solution and passed through a PTFE reaction coil (8 m x 0.5 mm) at 140°C. The mixture then merged with a stream (100 µL min-1) of 2% ammonium molybdate solution containing 0.36% ascorbic acid and 1.5 M H2SO4 and passed through a second PTFE coil (5 m x 0.5 mm) before the absorbance was measured at 880 nm. The calibration graph was rectilinear for 0.5 to 20 µg mL-1 of P; the detection limit was 16 ng mL-1. The method was used to determine P in chicken heart, eggs of salmon and yellowtail fish and in livers of cow, pig, chicken and fish.
Phosphorus Sample preparation Spectrophotometry PPB Heated reaction

"Determination Of N-methylcarbamate Pesticides In Liver By Liquid Chromatography"
J. AOAC Int. 1989 Volume 72, Issue 4 Pages 586-592
Ali MS

Abstract: A 21-g portion of bovine, porcine or duck liver was extracted with 200 mL of CH2Cl2 and the extract was dried (Na2SO4). After evaporation to 1 to 2 ml, the residue was dissolved in CH2Cl2 - cyclohexane (1:1; 7.5 ml) and cleaned up by gel-permeation chromatography on a column (60 x 2.5 cm) containing 60 g of BioBeads SX-3 resin (200 to 400 mesh), with CH2Cl2 - cyclohexane (1:1) as mobile phase (5.0 mL min-1). The eluate was evaporated and the residue was dissolved in CH2Cl2 and further cleaned up on an Aminopropyl Bond Elut cartridge, before transfer of residue to methanol and HPLC. Analysis was on a column (25 cm x 4.6 mm) of Zorbax C-8 (5 µm), with aqueous 12 to 70% acetonitrile over 30 min, then over 1 min to aqueous 80% acetonitrile (held for 8 min) as mobile phase (1.5 mL min-1). Post-column derivatization with phthalaldehyde was followed by fluorescence detection of 10 carbamate derivatives at 418 nm (excitation at 340 nm). Recovery was >80% with coefficient of variation of 17%; detection limits were 5 to 10 ppb.
Carbamates, N-methyl HPLC Fluorescence Sample preparation Post-column derivatization

"FAAS Determination Of Calcium And Magnesium In Gelatin Using The FIA Online Automatic Dilution Technique"
Lihua Jianyan, Huaxue Fence 1996 Volume 32, Issue 2 Pages 82-91
Zhang Min, Chen Shuyu, Lin Shuqin and Cheng Lin

Abstract: Sample (1.2 g) was soaked in 15 mL water for 15 min and digested with 1 mL concentrated HCl, 1 mL concentrated HNO3 and 4 mL H2O2. The digest was diluted with to 25 mL with water for FIA with flame AAS detection of Ca and Mg. Test solution was injected and carried to two sampling loops with a stream of water for alternating feeding, primary and secondary injection volumes being 21 and 70 µL, respectively. The solution was allowed to mix with a stream of 0.3% La solution prior to splitting into two streams by passing through two dilution tubes of 50 and 150 cm in length, respectively, with dilution of 87 to 233-fold, and detection. The peak B of the sets of signals was employed for measurement of Ca whereas the trough E for Mg. Determination was at µg/g level. RSD were 1.3-2.1%. The method was applied to the analysis of wheat, shrimp, pig liver and shrub leaves. Interference from phosphate was overcome. Sampling frequency was 96 runs/h.
Calcium Magnesium Sample preparation Spectrophotometry Interferences Dual injector Sample splitting