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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Commercial product

Classification: Commercial product -> herbicide

Citations 3

"Flow Injection Potentiometric Determination Of Paraquat In Formulations And Biological Samples"
Talanta 1998 Volume 47, Issue 5 Pages 1231-1236
Bahruddin Saad*, Marinah Ariffin and Muhammad Idiris Saleh

Abstract: A flow injection potentiometric method for the rapid determination of paraquat in herbicide formulations and biological samples is described. It is based on the utilization of a flow-through potentiometric detector containing polyvinyl chloride-immobilized octamethylcyclotetrasiloxane, a lipophilic plasticizer (tetra-n-undecyl 3,3',4,4'-benzophenone tetracarboxylate), and membrane additive potassium tetrakis(4-chlorophenyl)borate. The detector was minimally interfered by the presence of constituents such as Na+, K+, Ca2+, Mg2+, glucose, urea, and lactic and citric acids at physiol. levels, respectively. A good correlation between results of the proposed method and HPLC for the formulation samples was found while results for the determination of paraquat in biological samples such as urine, vomitus, and stomach washout was less satisfactory.
Paraquat Potentiometry Electrode Electrode Electrode Interferences Method comparison

"Spectrofluorometric Determination Of Paraquat By Manual And Flow Injection Methods"
Analyst 1998 Volume 123, Issue 7 Pages 1577-1581
Tomás Pérez-Ruíz, Carmen Martínez-Lozano, Virginia Tomás and José Fenoll

Abstract: The reaction involving the formation of a fluorescent charge-transfer complex between paraquat and benzaldehyde was studied in ethanol-water medium. In the presence of a large excess of benzaldehyde, the fluorescence intensity is linearly related to paraquat concentration. from 0.13 to 7.4 µg mL-1. The method can be easily adapted to a flow system using a two-channel manifold, the peak height being proportional to the paraquat concentration. over the range 1.6-22.3 µg mL-1. Manual and flow injection procedures were satisfactorily applied to the determination of paraquat in commercial herbicides, waters, soils and potatoes.
Paraquat Fluorescence Complexation

"Flow Injection Potentiometric Determination Of Atrazine In Herbicide Formulations"
Anal. Lett. 1998 Volume 31, Issue 5 Pages 777-791
Saad S. M. Hassan; M. N. Abbas; G. A. E. Moustafa

Abstract: A novel atrazinium-selective membrane sensor consisting of an atrazine phosphomolybdate ion-pair complex dispersed in a PVC matrix plasticized with dioctyl phthalate is described and electrochemistry evaluated under static and hydrodynamic modes of operation. The sensor is incorporated in a flow-through sandwich cell and used as a detector for flow injection determination of atrazine herbicide. The intrinsic characteristics of the detector in a low-dispersion manifold are determined and compared with those of a conventional-shaped sensor. In a phosphate buffer of pH 5, the detector exhibits a rapid near-Nernstian response (52.3 mV/decade) for atrazinium cation over the concentration. range 10^-2-10-5M. Concentrations as low as 0.3 µg atrazine/mL can be detected with an average recovery of 98.3% (mean standard deviation 0.6%), and the sample input rate is 60 sample per h. The sensor is used for determining atrazine in herbicide formulations, and in extracts of water and soil. No interferences are caused by herbicide diluents and excipients nor by most common anions and cations normally present in water and soil. The results compare favorably with data obtained by gas chromatography
Atrazine Potentiometry Electrode Electrode Electrode Sample preparation Interferences Method comparison