Recent developments and applications of QuEChERS based techniques on food samples during pesticide analysis

QuEChERS (quick, easy, cheap, effective, rugged, and safe) is one of the pre-treatment techniques that has gained tremendous popularity among researchers during pesticide analysis of food and agricultural samples. Since its inception, this method is considered particularly suitable and effective in the extraction of a wide range of compounds. Consequently, most of the methods, developed using QuEChERS involve extracting pesticides and contaminants from various food samples, particularly fruits, vegetables, and other food products. The QuEChERS technique involves two steps: A liquid liquid extraction and dispersive solid-phase extraction clean-up. The samples pre-treated using QuEChERS are clean enough to be analysed using gas or liquid chromatography. There are three common standard methods used during QuEChERS and these are the original QuEChERS, AOAC and the EN methods. In this review, recent developments in the QuEChERS technique are discussed as well as application of these techniques in the analysis of pesticides in food samples. Recently, many modifications of the QuEChERS technique have been effected during analysis of pesticides in food samples and are reviewed in this paper. Such modifications include the use of alkaline hydrolysis during analysis of acidic pesticides, inclusion of the freeze-out step when analysing food samples with high fat content as well as the use of new, effective sorbents such as Z-sep. The applications of the QuEChERS techniques to analyse pesticides in cereal, animal products as well as fruits and vegetables are also reviewed in this paper.