Sensitive determination of herbicides in food samples by nonaqueous CE using pressurized liquid extraction

Abstract

We have developed a method involving extraction with mixtures of solvents under pressure (pressurized liquid extraction (PLE)) for the determination of triazine herbicides in a series of samples from the food industry. The organic extracts obtained were subjected to a clean-up step with SPE, using Oasis MCX sorbents, after which they were analyzed by NACE. Potato was chosen as a representative matrix of horticultural products since it has a high water content. Spiked potato samples were used to optimize extraction conditions. In order to compare the results obtained with NACE, different studies were also conducted using HPLC. The detection limits in NACE were similar to those found with HPLC and were of the order of 10-15 microg/kg, depending on the analyte. Satisfactory results were obtained on applying the method proposed for the potato matrix (PLE with separation by electrophoresis) to other food matrices such as other tubercles, fruits, vegetables and cereals.

Ultrasonic solvent extraction and nonaqueous CE for the determination of herbicide residues in potatoes

“…The detection limits ranged from 1.7 lg/ kg for ametryn (Am) to 4.0 lg/kg for propazine (Pz). These values are of the same order of magnitude as those found in the analysis of Az and Sz in olives using matrix solidphase dispersion (MSPD) with GC-MS and LC-MS/MS [11], and they are even lower than those previously obtained by using PLE as an extraction technique prior to NACE analysis [21].…”

“…NACE has been shown to be an adequate mode for the electrophoretic separation of chloro-and methylthiotriazines [21]. Another aspect addressed here is the simplification of the steps involved in sample treatment (isolation, enrichment, clean-up) for the analysis of these matrices by using low-cost, inexpensive methodologies and instrumentation commonly used in routine laboratory analysis.…”

Modern Extraction Techniques for Pesticide Residues Determination in Plant and Soil Samples

“…Richter et al (2001) developed ASE for OPPs determination in carrot, Wennrich et al (2001) for OCPs in strawberry, apple, lettuce, tomato and kohlrabi, while Cho et al (2008) tested ASE for determination of iprodione, chlorpyrifos-methyl and endosulfan in kiwi. In 2007, Barriada-Pereira et al described it as a satisfactory method for determining 21 OCPs in lettuce, tomato, spinach, potato, tomato and bean, and in the same year Carabias-Martínez et al (2007) used ASE to determine triazines in potato, carrot, lettuce, bean, zucchini and orange. ASE was also used for determination of 28 pesticides in pear, potato and cabbage (Adou et al, 2001).…”

Pesticides: Herbicides and Fungicides

“…successfully used for the determination of triazine herbicide residues in potatoes [18,63] . Ultrasonic solvent extraction (USE) [18] and pressurized liquid extraction (PLE) [63] have been used to isolate the analytes from the sample matrix.…”