Abstract
Analytical chemistry determinations are not exempted from generating
environmental contamination. A variety of strategies are now being proposed to reduce
the impact on the environment caused by the different stages of the analytical process.
These strategies can focus on the different stages of the analysis, ranging from sample
collection and preparation to the acquisition and processing of analytical signals.
Sample preparation constitutes a basic and crucial stage in the success of any analytical
method and extraction is one of the most chosen techniques. Extractions often involve
the use of a large amount of harmful solvents that may damage the health of the
operator and the environment, into which these solvents are disposed of, often without
treatment. Therefore, new techniques have been applied in order to reduce the impact
of this procedure, also focusing on lowering the costs and complexity, always taking
into account the quality of the procedures. Current trends in green analytical chemistry
are directed towards simplification, miniaturization, and automation, also involving the
use of solvent-free, environmentally friendly procedures and, at the same time,
maintaining acceptable extraction efficiencies in a short time.
In this chapter, the fundamentals and technological advances in green extraction
systems will be presented. Through representative examples of different compounds in
different matrices, the advantages and limitations of different procedures will be
presented, including ultrasound-assisted extraction, pressurized solvent extraction,
microwave-assisted extraction, single drop liquid-liquid extraction, headspace
extraction, dispersive liquid-liquid microextraction, hollow-fiber liquid-phase
microextraction, micro-solid phase extraction, stir-bar sorptive extraction and stir-cake
sorptive extraction