Au nanoparticle decorated graphene oxide as a novel coating for solid-phase microextraction

Abstract

A novel solid-phase microextraction (SPME) fiber based on a stainless steel wire coated with Au nanoparticle decorated graphene oxide was prepared using a novel protocol. Coupled with gas chromatography-flame ionization detection (GC-FID), the extraction performance of the fiber was tested with aromatic hydrophobic organic chemicals as the model analytes. The fiber showed excellent extraction efficiency, good mechanical strength, and good stability in acid, alkali and organic solutions, and under high temperature. Effects of extraction time, extraction temperature, ionic strength and desorption conditions were investigated and optimized. The relative standard deviations for the single fiber repeatability and fiber-to-fiber reproducibility were less than 6.90 and 16.87%, respectively. Compared with graphene oxide/solid-phase microextraction fibers and Au nanoparticle/solid-phase microextraction fibers, the fiber has lower detection limits (≤60 ng L⁻¹) and a better linear range for all analytes. Correlation coefficients ranged from 0.9958 to 0.9993. The as-established SPME-GC-FID method was successfully used for two real natural samples, and recovery of the analytes spiked at 10 μg L⁻¹ ranged from 82.65% to 126.06%.