Forensic analysis towards green analytical chemistry: Developments and perspectives in sample preparation

Samples used for analysis are usually characterized by complex matrix composition as well as low concentrations of target analytes, thus requiring enrichment of analytes during sample preparation. The volume of samples is often limited. The compatibility of analytes with the analytical instrument is another important issue to consider before final analysis. These challenges can all be addressed by the application of proper sample preparation methods, which play a very important role in forensic analysis. Nowadays, many analytical extraction techniques exist; however, some, such as liquid–liquid extraction and solid-phase extraction, are of particular interest in forensic analysis. Nevertheless, considering the principles of Green Analytical Chemistry (GAC), these methods are far from its full implementation. The reduction of toxic chemical use, their volume, the reduction of waste produced, energy consumption, and the limitation of steps in general analysis are the most common issues related to sustainable practices. These challenges can be addressed through the implementation of single or combined strategies, including miniaturized sample preparation methods and the utilization of green solvents and sorbents. The introduction of GAC practices in forensic analysis can provide numerous benefits, such as enhanced worker safety, reduced waste, and cost savings. This is why the application of miniaturized techniques in forensic analysis has been widely adopted. This chapter focuses on commonly used microextraction techniques, green sorbents, and solvents applied in forensic analysis, with selected examples. We believe this will motivate future researchers to select appropriate materials and methods for future experiments and investigations.