What Color Is Your Method? Adaptation of the RGB Additive Color Model to Analytical Method Evaluation

Abstract

Evaluation of an analytical method is a fundamental problem in analytical chemistry, and it is never straightforward. In this article, we show a perspective for facing this issue using an original tool. We propose a model that allows one to evaluate any analytical method/procedure in a global manner. It refers to the RGB additive color model and uses three primary colors to represent three main attributes of the evaluated method: analytical performance - Red, compliance with the "green" chemistry principles - Green, and productivity/practical effectiveness - Blue. A final color of the method results from the additive synthesis of the primary colors. To simplify classifications, we propose the set of nine final colors of the method (white, magenta, cyan, yellow, red, green, blue, colorless/gray, and black). The model provides also a quantitative parameter, named the "method brilliance", which integrates all primary colors and treats them with varying importance, adjusted to the evaluation context and subjective user preferences. The evaluation is performed using standard Excel worksheets interpretable "at-a-glance" and adjustable to the particular method specifications. We discuss the opportunities offered by this model, potential obstacles, and related countermeasures, as well as future perspectives for its utilization. The paper shows also examples of using the model for the evaluation of real methods. We believe that the model can be applied not only in analytical science but also in other chemical subdisciplines.