A new need, quality, and sustainability (NQS) index for evaluating chemical analysis procedures using natural reagents

Abstract

The use of natural extracts as chemical reagents for flow analysis and downscaling techniques provides an alternative way to reduce risks to users and to the environment and is therefore considered a greener development in chemical analysis techniques according to the Green Analytical Chemistry (GAC) guidelines. The Green Analytical Procedure Index (GAPI) and the White Analytical Chemistry (WAC) have been used to evaluate some flow-based and downscaling procedures employing natural reagents in terms of environmental friendliness, analytical efficiency, and practicability. These flow-based and downscaling procedures are more environmentally friendly but less effective than the standard analytical ones. As recommended by Koel in 2016, these assessment aspects should be weighed against the need for applying the analysis. Furthermore, sustainable development has become an important issue worldwide. Thus, a new “Need, Quality, and Sustainability (NQS) index that assesses the analytical procedure in terms of ”Need“, the WAC as ”Quality“, and the Sustainable Development Goals (SDGs) as ”Sustainability“ is proposed. An approach for quantifying sustainability is also proposed. Application of this NQS index suggests that the use of natural reagents improves analytical procedures, especially in the need and sustainability aspects. The NQS index as an evaluation tool could assist in the development of analytical procedures addressing social needs, analytical performance, and global sustainability.