Rapid and Simple Method for Determination of Thiram in Fruits and Vegetables with High-Performance Liquid Chromatography with Ultraviolet Detection

Abstract

A rapid and sensitive HPLC-UV method was developed for determination of the dithiocarbamate thiram in fruit and vegetables. The method was based on extraction with a mixture of ethyl acetate and cyclohexane in an ultrasonic bath for 15 min. The analysis was done on an Apex II diol column in a straight (normal) phase HPLC system with UV detection. The average recoveries for spiked samples, 0.1−1.3 mg/kg, of apple, cucumber, lettuce, nectarine, plum, pear, and grapes were in the range of 73−86% with a relative standard deviation of 3.1−18%. Lower recoveries, 40−66%, were obtained for tomatoes, green pepper, raspberries, and strawberries, which might be explained by an enzymatic degradation of thiram. Limit of quantification was found to be 0.1−0.2 mg/kg for all tested matrices. Keywords: Thiram; HPLC-UV; fruits; vegetables; degradation

Solvent extraction followed by ultraviolet detection for investigation of tetramethylthiuram disulfide at soil-water interface

“…The linear regression equation and the correlation coefficient of the calibration curve drawn within the LDR are y = 0.037+0.075 and R 2 = 0.9753, respectively.The partition coefficient of thiram between CHCl 3 and water, determined by measuring the levels of thiram in the CHCl 3 phase after partitioning with the aqueous phase containing thiram, resulted in an average value of 5.86 ± 0.54 over 15 replicates within the initial concentration range of 1 ppm to 10 ppm in water. The minimum detection limit obtained in this method was comparable to that of the more sophisticated methods such as high performance liquid chromatography that employs sensitive detectors (Fernadez et al, 1996;Ekroth et al, 1998). The simplicity of the detection method developed is an added attraction for quantification of thiram.…”

“…For instance, thin layer densitometry of copper complexes of dithiocarbamates provides a simple and rapid means of their detection (Onuska, 1974). Extraction of thiram with cyclohexaneethyl acetate followed by HPLC with UV detection allows the detection at 0.1 -0.2 ppm level (Ekroth et al, 1998). Detection limits have been further enhanced to 3.8 ppt (parts per trillion) through a postcolumn reaction detector that employs UV photolysls with o-phthalaldehyde-2-mercaptoethanol followed by fluorometric determination (Miles and Moye, 1988).…”

Uptake and transportation behavior of a new fungicidal agent LH-2010A in cucumber plants

“…The flow rate was kept at 1.0 mL/min and the injection volume was 20 µL. The mobile phases were methanol and water (80/20, v/v) for LH-2010A, fluopicolide and metalaxyl, [13][14][15] and methanol and water (60/40, v/v) for thiram. The wavelengths of UV detection were 240 nm for LH-2010A, 225 nm for fluopicolide, 222 nm for metalaxyl and 310 nm for thiram.…”

Cost-Effective Tween 80-Capped Copper Nanoparticles for Ultrasensitive Colorimetric Detection of Thiram Pesticide in Environmental Water Samples

“…The European Union has limited the maximum allowable concentration for thiram in fruits, fresh or frozen, tree nuts about 0.1-10 mg.kg -1 [9]. Currently, various analytical techniques for the detection of thiram residue, for instance, spectrophotometry combined with solid-phase extraction [10,11], chromatographic methods (LC-MS) [12], LC coupled with tandem mass spectrometry (LC-MS/MS) [13], gas chromatography (GC) [14], enzyme-linked immunosorbent assay (ELISA) [15], and high-performance liquid chromatography (HPLC) with ultraviolet detection [16]. Despite the advantages, most of these techniques require time-consuming sampling and skilled personnel to operate complex and costly instrumentation, have lengthy processing, and are unable to widely apply these techniques, especially in the on-site analysis.…”