Ultrasound-assisted cloud point extraction: a review

Ultrasound-assisted cloud point extraction (UA-CPE) has become a highly efficient and promising alternative for analyte separation and pre-concentration in various types of samples of interest in diverse branches of science and technology. This review article addresses the application of UA-CPE as a sample processing technique that meets several requirements recommended by Green Analytical Chemistry, such as the use of small amounts of extraction reagent (the surfactant), which exhibits low flammability, and generally low toxicity, the generation of low amounts of waste, environmental safety, extraction speed, and low energy consumption. The basic principles of the technique will be discussed for a better understanding. Additionally, studies on the determination of metals, inorganic and organic analytes, published in the last ten years, will be discussed to illustrate their potential and applicability. The application of UA-CPE in the speciation analysis of metallic species and future trends involving the technique will also be addressed.