Self-assembly of dodecyl groups on titania nanorods coated a titanium fibre for rapid and efficient solid-phase microextraction of polycyclic aromatic hydrocarbons from environment water

Abstract

ABSTRACT A new organic-inorganic hybrid coated titanium fibre was developed via self-assembled modification for rapid and efficient solid-phase microextraction (SPME). Oriented titania nanorods (TiO2NRs) were in situ grown on the Ti wire as a fibre substrate through direct electrochemical anodisation. Subsequently, dodecyl groups were chemically bonded to the surface of TiO2NRs via self-assembly of n-dodecyltrimethoxysilane. The dodecyl-functionalised TiO2NRs coated Ti fibre was used to extract representative aromatic compounds coupled to high-performance liquid chromatography with UV detection. The new fibre exhibited excellent extraction efficiency and selectivity for the studied polycyclic aromatic hydrocarbons (PAHs) compared to commercial polydimethylsiloxane and polyacrylate fibres. The influential factors affecting the SPME process of PAHs were investigated and optimised. Under the optimised conditions, the developed method presented dynamic linear ranges from 0.03 to 500 μg·L−1 with correlation coefficients higher than 0.999 and limits of detection from 0.006 to 0.57 μg·L−1. Relative standard deviations (RSDs) varied between 3.51% and 4.93% and between 4.17% and 5.23% for intra-day and inter-day measurements with one single fibre, respectively. RSDs for the fibre-to-fibre reproducibility from 4.26% to 8.65% were achieved. The developed method was successfully applied to the selective preconcentration and determination of target PAHs in different environmental water samples. The relative recoveries from 89.62% to 113.1% were obtained with RSDs below 8.53%. Moreover, this fibre can be used over 200 times and fabricated in a precisely controllable manner.