Emerging green solvents and their applications during pesticide analysis in food and environmental samples.

Green solvents reduce secondary pollution of the environment during pesticide pre-concentration in food and environmental matrices. Ionic liquids are among the green solvents that are widely used during pesticides analysis. Their physico-chemical properties can be easily modified by changing the cation/anion combinations in their structures. This paper critically reviews the application of ionic liquids during pre-concentration of pesticides in food and environmental samples. Another group of green, designer solvents is composed of deep eutectic solvents. They are synthesised simply by mixing hydrogen bond donors and hydrogen bond acceptors. Their contributions during pesticide pre-concentration are reviewed critically in this paper. The use of supramolecular solvents during pesticide pre-concentration is gaining popularity among researchers. They are green, water-immiscible solvents composed of three-dimensional amphiphilic aggregates and their applications during pesticide pre-concentration are reviewed in this paper. The amount of chemicals used during pesticide analysis can be reduced by using switchable solvents. This paper also gives a critical review of the applications of switchable solvents during micro-extraction of pesticides in food and environmental samples. In addition, the challenges associated with the use of these green solvents are discussed in this review as well as the future prospects.