ABSTRACT
The selectivity of a material in sample preparation can be toward a target analyte or a group of analytes with related properties. The conditions used during the sample preparation process should be carefully optimized, enhancing their ability to support an effective cleanup without analyte losses. Significant progress has been achieved in the development of novel materials for sorptive extraction techniques, with selectivity becoming an additional requirement during its development. Molecularly imprinted polymers (MIPs), and mixed-mode polymeric materials, can be categorized as selective materials. The selectivity of MIPs arises from the synthetic procedure used, whereby functional monomers and a cross-linker agent are polymerized in the presence of the target compound that controls the sizes and functionality of the cavities during the polymerization. Ion-exchange sorbents are a good alternative for extracting ionic or ionizable compounds, since they are based on ionic interactions. The development of materials that improve selectivity in the sample preparation process is a growing research topic in environmental analysis.
