An electrospun polyamide/graphene oxide nanocomposite as a novel fiber coating

Abstract

In this study, a novel solid phase microextraction fiber coating based on a polyamide–graphene oxide nanocomposite was prepared using an electrospinning technique on stainless steel wire as a robust substrate. Scanning electron microscopy images showed the high porosity of the synthesized polyamide–graphene oxide nanocomposite and the diameter of nanofibers to be in the range of 100–250 nm. The method feasibility was studied by the extraction of polycyclic aromatic hydrocarbons as model compounds from water samples. The important factors of the electrospinning procedure and extraction processes such as the polymer concentration, amount of graphene oxide nanoparticles, power voltage, electrospinning time, extraction temperature and time, ionic strength and desorption conditions were studied and optimized. The developed method is fast and sensitive, providing sub and low ppt detection limits, a limit of detection of 0.7–1 ng L⁻¹ and a limit of quantification of 2–5 ng L⁻¹ at an equilibrium time of 15 minutes. A wide linearity in the range of 5–2000 ng L⁻¹ with R > 0.9995 was also obtained. The repeatability of the method was assessed at 100 ng L⁻¹ and a relative standard deviation of 5–10% was achieved. Finally, the developed method was applied to real water samples and the relative recoveries were found to be in the range of 89–101%, showing no matrix effect.