Advances in thin film micro-extraction (TFME) of analytes using metal-organic frameworks, molecularly imprinted polymers, and polysaccharide composites as extraction phases

Thin film micro-extraction is a sample preparation method that can be used to pre-concentrate a variety of analytes in complex matrices. TFME, compared to other micro-extraction techniques, has enhanced sensitivity for analytes since the extraction phase is spread over a larger surface area. This facilitates rapid mass transfer and diffusion of analytes during the micro-extraction process. In addition, TFME is generally a solvent-free technique, and this minimises the generation of secondary pollutants during the extraction process. The greenness of the TFME technique can be greatly enhanced by the careful selection of the extraction phases. Some of the extraction phases that stand out include molecularly imprinted polymers, metal–organic frameworks, and polysaccharide composites. This review explores the application of these green and highly selective extraction phases during the TFME technique. The challenges as well as the future prospects associated with the use of these TFME extraction phases are well articulated in this paper.