Perspectives on the replacement of harmful organic solvents in analytical methodologies: a framework toward the implementation of a generation of eco-friendly alternatives

Volatile organic solvents derived from non-renewable fossil feedstocks are commonplace in analytical laboratories. In spite of their convenient performance in countless unit operations, their environmental, health and safety issues represent a major area of concern. The progressive replacement of organic solvents obtained from fossil resources by eco-friendly alternatives would involve remarkable advances within the framework of green analytical chemistry, while avoiding future uncertainties regarding forthcoming regulations. This perspective tackles the problem of organic solvent use in analytical methodologies, providing relevant information for solvent selection and identifying a range of solvents derived from natural and/or renewable resources, namely bio-based molecular solvents, ionic liquids composed wholly of biomaterials and natural deep eutectic mixtures that could potentially be exploited toward advanced, more benign, analytical methodologies. In addition, physicochemical properties are provided, and a number of challenging aspects to be considered in the implementation of eco-friendly alternatives are evaluated.