Evaluation of Eco-friendly Analytical Methods Using Green Chemistry Metrics

Abstract

Green analytical chemistry advocates for the reduction of hazardous chemicals and reagents, the use of energy-efficient instruments, and the minimization of waste production. In recent years, new trends in developing analytical methods have focused on miniaturization of the sample preparation systems, development of solvent-free or solvent-reduced extraction techniques, and safe and less toxic solvents. The twelve principles of Green Analytical Chemistry stand as basic guidelines for improving the environmental friendliness of analytical procedures. However, in some cases, non-green steps are still inevitable; thus, analysis of the “greenness” of analytical procedures is necessary in order to identify, characterize, and minimize environmental and occupational exposure associated with these procedures. This objective is supported by several analytical assessment tools, which include the Analytical Eco-Scale, Green Analytical Procedure Index (GAPI), and Analytical Greenness Metric (AGREE). All these approaches assess different aspects of an analytical method with respect to its environmental friendliness. The review discusses the key metrics principles and, by presenting examples, their application to a wide range of analytical methods. Besides, advantages and limitations are outlined from a practical user’s perspective. The review is expected to foster new ideas and further progress in developing greener analytical approaches.