Mesoporous silica sorbent with gold nanoparticles for solid-phase extraction of organochlorine pesticides in water samples

In this work, a novel sorbent, based on UVM-7 mesoporous silica doped with Au, has been proposed for organochlorine pesticides extraction. Cartridges containing this material have been applied to the preconcentration of 20 pesticides from water samples, through a solid-phase extraction (SPE) protocol, with their later determination by gas chromatography with an electron capture detector. First, UVM-7 materials were properly characterized by X-ray diffraction, N-2 adsorption-desorption, electron microscopy techniques, and UV-Vis spectroscopy, thus confirming their structure and Au incorporation. After optimization of main extraction parameters, recoveries in the range of 80-110% were obtained for most of the analytes, with enrichment factors comprised between 275 and 430. The obtained sensitivity was comparable with other reported methods, with limits of quantification in the range of 0.3-20 ng L-1, thus allowing the determination of these compounds according to European legislation. The developed method has been successfully applied to the analysis of real spiked samples in comparison with a reference method, thus being this sorbent an alternative for organochlorine pesticide enrichment, through a simple, reusable, cheap, and environmentally friendly SPE procedure. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A novel sorbent based on UVM-7 mesoporous silica doped with gold has been proposed for the extraction of organochlorine pesticides. The sorbent showed good recovery rates for most analytes and comparable sensitivity with other methods, allowing for the determination of compounds according to European legislation. This environmentally friendly and cost-effective solid-phase extraction method has proven to be an alternative for pesticide enrichment in water samples.