A review on extraction, preconcentration and speciation of metal ions by sustainable cloud point extraction

The cloud point extraction (CPE), a surfactant-based extraction and preconcentration procedure of metal ions in trace level, has become an attractive area of research in the field of analytical chemistry in last few decades. CPE is greener alternative to the conventional separation techniques as well as an excellent speciation tool even in ultra-trace scale of the analytes. The article demonstrates various aspects of CPE, and its recent developments like micro-cloud point extraction (MCPE), displacement cloud point extraction (DCPE) and dual cloud point extraction (d-CPE), over the period 2000 to till date. In particular the article focuses on the extraction and speciation of metal ions like Al, Cr, Fe, Co, Ni, Cu, As, Se, Cd, Sb, Hg and Pb by CPE. The review also discusses extraction of anionic species like chloride, nitrate, nitrite, sulphide, etc., by CPE. Researches on nanoparticles in modern day science is increasing in leaps and bounds, at the same time a matter of concern from environmental aspect. Therefore, we have also included a brief discussion on the extraction and determination of nanoparticles by CPE.

Automated summary

Cloud point extraction (CPE) is a greener alternative to conventional separation techniques in the field of analytical chemistry. This article provides an overview of various aspects of CPE and its recent developments, focusing on the extraction and speciation of metal ions and anionic species. The article also briefly discusses the extraction and determination of nanoparticles by CPE.