Various eco-friendly and green approaches in thin film microextraction techniques for sample analysis - a review

Thin film microextraction (TFME) has received much attention because of its high surface area to volume ratio in the extraction phase, short extraction time, high adsorption ability, and minimal solvent use. Thin film micro-extraction is used for preconcentration of a wide range of analytes in different matrices, including pharmaceutical, pesticide, food, biological, and environmental. The extraction phase is extremely important among the various influencing parameters in TFME. The use of an effective green extraction phase in TFME improves extraction performance. This review briefly evaluates various green approaches in the TFME technique, including ionic liquid-based, deep eutectic solvent-based, biopolymer-based, and biochar-based extraction phases. The discussed approaches were more green and effective than traditional TFME because of the sorbents' relative biodegradability, sustainability, cost-effectiveness, and environmental friendliness. Each TFME approach has been discussed in light of recent research in order to explore its benefits fully.