Recent green approaches in liquid-phase microextraction

Abstract

The miniaturization of conventional extraction techniques, particularly microextraction methods, has led to a reduction in the use of hazardous reagents and waste. However, the continued use of toxic solvents and materials, along with time-consuming sample preparation processes, negatively impacts the overall sustainability of these methods. As a result, there is growing interest in exploring greener alternatives. This review highlights the most promising green solvents for liquid-phase microextraction, including (natural) deep eutectic solvents, lowtoxicity ionic liquids, surfactants, micellar solvents, and bio-based solvents, emphasizing their applications in innovative sample preparation techniques in the last five years. Particular emphasis is placed on their use in automated and semi-automated systems, in line with the increasing role of automation in Analytical Chemistry. Selected applications have been carefully reviewed and discussed to illustrate key advances in the use of green solvents and automation for extracting a wide range of compounds from various matrices. In addition, future perspectives are outlined to guide further development of liquid-phase microextraction in alignment with current trends in green sample preparation.