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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Leaves

Classification: Plant -> tomato -> leaves

Citations 3

"Atomic Absorption Spectrometric Analysis Of Solids With Online Microwave-assisted Digestion"
J. Anal. At. Spectrom. 1992 Volume 7, Issue 7 Pages 1085-1089
V. Carbonell, A. Morales-Rubio, A. Salvador, M. de la Guardia, J. L. Burguera and M. Burguera

Abstract: A description is given of a procedure for online microwave-assisted digestion of solid samples prior to analysis by flame AAS as described previously (Anal. Chim. Acta, 1990, 238, 417). A slurry of the sample is transported in HNO3 - H2O2 (1:1) to extract Cu and Mn quantitatively in a few min. Digestion times vary from 4 min for sewage sludges to 2 min for matrices like artichoke. Detection wavelengths were 324.7 nm for Cu and 279.5 nm for Mn. A closed flow injection system allows digestion to be conducted online. Sample flow rate was 2.8 mL min-1. Over 15 samples h-1 can be analyzed using the procedure which allows for sequential treatment of different samples. A procedure was developed for the online microwave-assisted digestion of solid samples and their anal. by flame atomic absorption spectrometry. The method involves the transport of a slurry of the sample in a 1+1 mixture of concentrated HNO3 and H2O2, which provides quant. extraction of Cu and Mn in a few minutes. Real samples of sewage sludges dispersed in 20 mL of HNO3 and H2O2 can be digested in 4 min and other matrixes, such as artichoke and diet samples dispersed in 10 mL of HNO3 and H2O2 are digested in only 2 min. A closed flow injection system permits the online digestion to be carried out; the use of two interconnected injection valves allows the measurement of standards during the digestion of samples. The method permits the anal. of more than 15 samples per h and provides accurate results, as demonstrated by the anal. of certified samples of sewage sludges and tomato leaves.
Copper Manganese Sample preparation Spectrophotometry Microwave Online digestion Slurry Reference material

"Uranine-sensitized Chemiluminescence For Alternative Determinations Of Copper(II) And Free Cyanide By The Flow Injection Method"
Anal. Chem. 1989 Volume 61, Issue 14 Pages 1505-1510
Xing Zheng Wu, Masaaki Yamada, Toshiyuki Hobo, and Shigetaka Suzuki

Abstract: The chemiluminescence system Cu(II) - CN- - fluorescein (I) was applied in the determination of Cu(II) and free CN- by flow injection analysis with a single-flow system. The weak light emission produced by Cu(II) - CN- in the presence of dissolved O was effectively sensitized by I in aqueous propan-2-ol. Under optimum conditions, viz, 0.4 mM I, 50 µM CN- (for Cu mode) or 10 µM Cu(II) (for CN-), 80% propan-2-ol and a flow rate of 4 mL min-1, the determination limits were 6 and 5 pg for Cu(II) and CN-, respectively. The calibration graph was rectilinear over three orders of magnitude. The coefficient of variation (n = 10) was 3.1 and 3.3% for 30 nM Cu(II) and CN-, respectively. The method was applied in the analysis of tomato leaves and tap water for Cu and river water for CN-.
Copper(II) Cyanide, free Chemiluminescence Optimization

"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