Recent advances in microextraction techniques using sustainable green solvents for mass spectrometry analysis

Sample preparation based on extraction techniques plays a crucial role in the entire analytical process, as it ensures accurate and reliable analysis of analytes by eliminating matrix interferences. However, conventional sample preparations are considered the labor-intensive, time-consuming part of analysis, relying on the extensive use of harmful organic solvents. In line with green analytical chemistry concepts, implementing sustainable green solvents in microextraction techniques for sample preparation contributes significantly to the development of green analytical methodologies. Taking advantages of the solvation properties and greenness merits, these sustainable green solvents can be tailored as promising extractants for specific microextraction tasks, facilitating an efficient and environmental-friendly sample preparation prior to instrumental analysis. In this review, we provide a concise summary of recent advances in the prominent sustainable green solvents (such as ionic liquids, deep eutectic solvents, natural deep eutectic solvents, amphiphilic solvents, switchable solvents, sub-/supercritical fluids, and bio-based solvents) utilized in microextraction techniques, and their applications coupled with various mass spectrometric approaches for highly selective and sensitive analysis. Finally, we discuss the potential future outlooks in this field.