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: Plant -> herb -> parsley

Citations 2

"High Performance Liquid Chromatographic Method For Determination Of Six N-methylcarbamates In Vegetables And Fruits"
Bull. Environ. Contam. Toxicol. 1984 Volume 33, Issue 5 Pages 538-547
Keh-Chuh Ting, Peng K. Kho, Anna S. Musselman, George A. Root and George R. Tichelaar

Abstract: The sample was chopped and blended with acetonitrile, the aqueous layer was filtered off and NaCl was added to the filtrate with shaking. The mixture was centrifuged and the upper acetonitrile layer was removed and evaporated to dryness. For certain crops (e.g., citrus fruit, celery heart, mint, cilantro, parsley and parsnip) a clean-up step on Florisil was included at this point. The final methanolic solution containing the pesticides was analyzed on a column (25 cm x 4.6 mm) of Ultrasphere ODS (5 µm) equipped with a pre-column of octadecyl material on glass beads. Elution was effected with a linear gradient of acetonitrile - water (1:19 to 7:3 in 12 min, then to 1:19 in 1 min, maintained for 3 min) at a flow rate of 1.5 mL min-1. Post-column derivatization with phthalaldehyde was employed and the fluorescent products were detected at 455 nm (excitation at 360 nm). The HPLC system is described in detail and illustrated. Recovery data for oxamyl, methomyl, aldicarb, carbofuran, carbaryl and methiocarb are tabulated.
Carbamates, N-methyl Pesticides Oxamyl Methomyl Aldicarb Carbofuran Carbaryl Methiocarb HPLC Fluorescence Post-column derivatization Glass beads

"Flow Injection Determination Of Nitrate In Vegetables Using A Tubular Potentiometric Detector"
J. Agric. Food Chem. 1995 Volume 43, Issue 3 Pages 704-707
Jose L. F. C. Lima, Antonio O. S. S. Rangel, and M. Renata S. Souto

Abstract: Dried powdered vegetable was extracted by the method of Mitrakas and Alexiades (Mikrochim. Acta, 1990, 1, 7) and the extract was injected into a carrier stream (6 ml/min) of 1 µM-KNO3 in extractant solution (10 nM-lead acetate, 5 mM lead oxide and 10 mM sodium acetate) in a low dispersion FIA system. The flow passed through a tubular nitrate ISE with (4,7-diphenylphenanthroline) nickel(II) dissolved in o-nitrophenyl octyl ether immobilized in a PVC membrane and without an inner reference solution (preparation details given). The calibration graph was linear for 0.4-40 mM nitrate with a detection limit of 28 µM. Recoveries were 93.8-104% for nitrate in parsley, lettuce and spinach with RSD of 3%. A flow injection system with potentiometric detection for the determination of nitrate in vegetables was developed. For this purpose a tubular nitrate ion-selective electrode with the ion-exchanger system [(4,7- diphenylphenanthroline)nickel(II) dissolved in o-nitrophenyl octyl ether] immobilized in a PVC membrane and without inner reference solution was prepared. The flow injection manifold incorporating the tubular electrode was used for the determination of nitrate in vegetables (lettuce, parsley, and spinach), using a mixture of lead acetate, lead oxide, and sodium acetate as nitrate extractant, ionic strength adjustor, and interference suppressor solution. The quality of the results obtained by the proposed methodology was assessed by comparing them with those provided by a conventional potentiometric methodology and also through recovery tests (recoveries from 94 to 104% were found). A sampling rate of 120 samples per hour was achieved with a relative standards deviation lower than 2%.
Nitrate Electrode Electrode Potentiometry Electrode Method comparison Interferences