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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Commercial product

Classification: Commercial product -> pesticide

Citations 3

"Chemiluminescent Flow Sensor For The Determination Of Paraoxon And Aldicarb Pesticides"
Anal. Chim. Acta 1994 Volume 294, Issue 1 Pages 35-42
Aldo Roda, Pavel Rauch, Elida Ferri, Stefano Girotti*, Severino Ghini, Giacomo Carrea and Roberto Bovara

Abstract: Aldicarb (I); 60 µL containing up to 100 µg/ml of I or paraoxon (II) also containing 5 mM acetylcholine and electric-eel acetylcholinesterase (III) at 20 miu in Tris hydrochloride of pH 8/DMSO was injected into a stream of phosphate buffer of pH 8 (0.1 ml/min) and merged with the chemiluminescent reagent (0.2 ml/min) of 56 µM-luminol in 0.2 M Tris hydrochloride of pH 8 and fed through a packed column (3 cm x 2 mm i.d.) of choline oxidase/peroxidase (16:1) immobilized on Eupergit C which was sited in front of the photomultiplier tube of the luminometer. With operation at a flow that enabled an incubation time of 1 h, the detection limits were 4 µg/l for I and 0.75 µg/l for II (RSD, n = 10, 6.6 and 3.8%, respectively) and a throughput of up to 15 samples/h was possible. Loading of III in solution enabled much improved detection limits, relative to immobilization of III on the Eupergit C column.
Aldicarb Paraoxon Chemiluminescence Sensor Immobilized enzyme Column

"Determination Of Carbaryl In Pesticide Formulations By Fourier Transform Infrared Spectrometry With Flow Analysis"
Analyst 1993 Volume 118, Issue 8 Pages 1043-1048
Máximo Gallignani, Salvador Garrigues, Annabelle Martínez-Vado and Miguel de la Guardia

Abstract: Manifolds for continuous-flow and stopped-flow analysis are illustrated. A solution of the sample (containing 40-60 mg of carbaryl in 10 mL of CH2Cl2) was filtered or centrifuged. For continuous-flow measurement, 300 µL of the solution was injected into a stream (0.81 ml/min) of CH2Cl2, and, in a flow cell of path length 0.117 mm, the FTIR spectrum between 2000 and 1500 cm-1 was recorded continuously as a function of time, the baseline being measured between 1850 and 1650 cm-1. The peak height at 1747 cm-1 was used for quantitation. In the stopped-flow mode, five spectral scans for the CH2Cl2 solution of the sample were accumulated and the absorbance at 1747 cm-1 was recorded above the baseline from 1850 to 1650 cm-1. The range of the continuous-flow method was 0.25-10 mg/ml and the sampling frequency was 53/h; corresponding values for the stopped-flow method were 0.13-10 mg/ml and 90/h. Excipients in pesticide formulations are not dissolved by CH2Cl2. Results agreed well with those obtained by extraction-fluorimetry (details given) but those by FTIR spectrometry were more reproducible.
Carbaryl Spectrophotometry Sample preparation Stopped-flow Extraction Method comparison

"The Use Of Mobile Phase Additives In The Determination Of 55 (polar) Pesticides By Column Liquid Chromatography-thermospray Mass Spectrometry"
Int. J. Environ. Anal. Chem. 1994 Volume 54, Issue 2 Pages 119-145
Vreeken, R.J.;Van Dongen, W.D.;Ghijsen, R.T.;Brinkman, U.A.T.

Abstract: The effect has been studied of various additives to FIA carrier streams or LC eluents on the sensitivity and selectivity of the detection of 55 pesticides in the positive-ion or negative-ion mode. The additives used were ammonium acetate, ammonium formate, triethylammonium formate, tripropylammonium formate and chloroacetonitrile in carriers/eluents of aqueous ~e;50% acetonitrile; the ion modes used (where applicable) for each combination in filament-off, filament-on and discharge ionization are tabulated. The presence of each additive provided useful additional information. Discharge ionization was preferred in both the positive- and negative-ion modes because of the more selective fragmentation and lower detection limits that were obtained.
Pesticides LC Mass spectrometry