Ordered Mesoporous Silicas in Modern Versions of Solid-Phase Extraction

Abstract

The review systematizes information on nanostructured materials used in solid-phase extraction (SPE) and its modern versions. The main attention is paid to the consideration of nanostructured analogues of MCM-41 and SBA-15 both in classical SPE and modern versions of solid-phase microextraction, matrix solid-phase dispersion microextraction, dispersive solid-phase extraction, and magnetic SPE. The use of silicas with a hexagonal and a cubic mesophase structure makes it possible to significantly increase the recovery of analytes and improve the performance characteristics of determining both metal ions and biologically active substances in complex multicomponent matrices of real samples. An abnormally high surface area (up to 1000 m²/g and more), adjustable mesopore size, ease of modification by attaching functional groups allow a significant increase in the selectivity of solid-phase materials compared to traditionally used silicas and polymeric ion exchangers. The advantages of ordered silicas used at the stage of the extraction and preconcentration of analytes in solid-phase extraction versions, as well as in the chromatographic separation of substances similar in nature, make it possible to expand the range of linearity of the analytical signal of the analytical methods used, and the limits of detection for ions and molecules can be reduced to the level of ng/mL, ng/g.