Preparation and characterization of vinyl-functionalized mesoporous organosilica-coated solid-phase microextraction fiber

Abstract

Vinyl-SBA-15 mesoporous organosilica was synthesized and used as coating material of solid-phase microextraction (SPME) by two coating techniques (direct coating and sol-gel). The synthesized vinyl-SBA-15 organosilica had highly ordered mesoporous structure, good thermal stability and a specific surface area of 688 m² g⁻¹. The fibers prepared by two methods were evaluated by the extraction of non-polar compounds (BTEX, benzene, toluene, ethylbenzene, o-xylene) and polar compounds (phenols). The results showed that the vinyl-SBA-15 fibers prepared by two methods exhibited high thermal stability (310 °C for direct-coated and 350 °C for sol-gel) and excellent solvent durability in methanol and acetonitrile. The fibers also presented much better extraction performance for both polar compounds (phenols) and non-polar compounds (BTEX), compared to commercial polydimethylsiloxane (PDMS) fiber, as well as wide linear ranges, low detection limits (0.008-0.047 μg L⁻¹ for BTEX, sol-gel; 0.15-5.7 μg L⁻¹ for phenols, direct-coated), good repeatabilities (RSDs less than 5.4% for BTEX) and satisfying reproducibilities between fibers (RSDs less than 5.8% for BTEX). The self-made fibers were successfully used for the analysis of BTEX and phenols in three aqueous samples including tap water, mineral water and lake water, which demonstrated the applicability of the vinyl-SBA-15 fibers.