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 -> tobacco -> leaves

Citations 4

"Determination Of Nicotine By Reagent-injection Flow Injection Photometric Method"
Talanta 1998 Volume 47, Issue 4 Pages 833-840
Jingfu Liu* and Yingdi Feng

Abstract: Nicotine was determined by a reagent-injection flow injection photometric method making use of the Koing reaction. The applicability of four color reagents, aniline, barbituric acid, pyrazolone and sulfanilic acid, were evaluated and the sulfanilic acid was selected. The linear range, detection limit, RSD, and sample throughput of the established sulfanilic acid method were 0-10 mg L-1, 0.12 mg L-1, 0.7% and 50 h-1, respectively. Background absorption from sample matrix was eliminated by the reagent-injection flow injection technique. The proposed method was applied to determine nicotine in tobacco and urine samples with satisfactory results.
Nicotine Spectrophotometry Reverse Optimization

"Determination Of Trace Amounts Of Cobalt By Flow Injection With Spectrophotometric Detection"
Analyst 1994 Volume 119, Issue 7 Pages 1553-1556
Krystyna Pyrzynska, Zofia Janiszewska, Joanna Szpunar-Lobinska and Merek Trojanowicz

Abstract: A flow injection system featuring a glass microcolumn (2 cm x 2 mm i.d.) packed with alumina was used to pre-concentrate Co online as cobalt-nitroso-R-salt. Elution was effected with 0.1 M NaOH. Detection was at 520 nm with use of a Hewlett-Packard Model 8452A spectrophotometer. The detection limit for a 10 min pre-concentration was 3.5 ng/ml and the RSD at 20 ng/ml was 3.1%. The main interference was from Cu(II) which can be removed as sulfide. The method was used to determine Co in oriental tobacco leaves and pyrite ore certified reference materials.
Cobalt Spectrophotometry Reference material Preconcentration Interferences Alumina Column

"Electrocatalysis And Detection Of Amino-sugars, Alditols And Acidic Sugars At A Copper-containing Chemically Modified Electrode"
Anal. Chem. 1989 Volume 61, Issue 20 Pages 2258-2263
Sunil V. Prabhu and Richard P. Baldwin

Abstract: The use of the electrode described previously (Anal. Abstr., 1990, 52, 4J112) for the oxidative detection of simple sugars has been extended. Cyclic voltammetric scans for the compounds showed a broad oxidation in the region of +0.4 to +0.6 V vs. Ag - AgCl. When used in flow injection analysis and LC, detection limits were in the pmol to nmol range. With flow injection the coefficient of variation (n = 60) for 10 µM-gluconic acid was 4.9% and in the analysis of a tobacco leaf extract by LC, the standard deviation, e.g., for 3.7% of glucose was 0.2%.
Gluconic acid Electrode Voltammetry Detection limit Catalysis

"Simultaneous Determination Of Phosphorus, Potassium And Sodium In Plants By Flow Injection Analysis"
Fenxi Huaxue 1992 Volume 20, Issue 2 Pages 196-198
Wu, J.;Cai, Y.;Rao, Z.

Abstract: Air-dried tobacco leaves (0.5 g) were washed and ashed at 500°C for 4 h and the ash was dissolved in and diluted with 1% HCl to 25 mL. A 40 µL portion of the solution was injected into a water carrier stream and merged with a stream of 0.02 M (NH4)6Mo6O24 containing 1 M HCl before mixing with a stream of 3 mM SnCl2 containing 1 M HCl (all streams were at 3.6 mL min-1). Phosphorus was detected spectrophotmetically at 620 nm and K and Na were detected upstream by flame photometry. Beer's law was obeyed for 1 to 4 µg mL-1 of P, 3 to 60 µg mL-1 of K and 6 to 40 µg mL-1 of Na; corresponding coefficient of variation were 1.4, 1 and 1.1%. Results were in good agreement with those by ICP-AES.
Phosphorus Potassium Sodium Spectrophotometry Spectrophotometry Dual detection Method comparison