2. Greening analytical procedures
Remote sensing and direct measurements on untreated samples
are the green dream of analysts and many strategies have been
developed for the analysis of target compounds based on the use
of spectroscopy and electroanalytical signals [17] and image processing
[18]. However, in most analytical methodologies, sample
treatment is an unavoidable step and the use of a classical methodology,
similar to that in Fig. 2 (sampling, sample transport and
sample preparation before the acquisition of analytical measurements)
is absolutely necessary. Typical sample-treatment methods
include homogenization, filtration, centrifugation, clean-up, analyte
extraction, preconcentration and/or derivatization. On evaluating
the environmental impact of methods, sample preparation is,
by far, the most challenging step regarding both the main
features and the green parameters of the methods. Sample dissolution
and analyte extraction involve the use of reagents and
energy, and special care must be taken to select the procedure as
simple as possible at room temperature, and the least hazardous
reagents. In this context, options for greening methods must be
based on avoidance of the use of toxic reagents and a strong
reductions in consumption of energy and reagents, waste generation,
time taken and operator effort. As a result, minimization and
automation have been the basic tools for greening the analytical
methods.