Controlled growth of a porous hydroxyapatite nanoparticle coating on a titanium fiber for rapid and efficient solid-phase microextraction of polar chlorophenols, triclosan and bisphenol A from environmental water

Abstract

Microporous titania (TiO₂) was in situ grown on a titanium (Ti) wire as a fiber substrate through direct electrochemical anodization in sulfuric acid containing fluoride. Subsequently hydroxyapatite nanoparticles (HANPs) were fabricated on the template support of TiO₂ micropores (TiO₂MPs) via sol–gel technology. The resulting fiber coating was used for solid-phase microextraction (SPME) of aromatic compounds coupled to high-performance liquid chromatography (HPLC) with UV detection. This fiber exhibited excellent extraction efficiency and selectivity for phenolic compounds compared to commercial polydimethylsiloxane and polyacrylate fibers. Different factors affecting the extraction performance for phenolic compounds were examined and optimized. The proposed method presented linear ranges from 0.05 to 500 μg L⁻¹ with correlation coefficients higher than 0.999 and limits of detection from 0.012 to 0.14 μg L⁻¹. Intra-day and inter-day relative standard deviations (RSDs) varied between 3.85% and 4.94% and between 4.10% and 5.38% for the proposed method with the single fiber, respectively. RSDs for fiber-to-fiber reproducibility from 4.25% to 7.65% were achieved. This newly fabricated fiber can be used over 200 times and fabricated in a precisely controllable manner. The proposed method was successfully applied to the selective enrichment and determination of trace chlorophenols, triclosan and bisphenol A in river water and domestic sewage. Relative recoveries from 89.62% to 110.2% were obtained with RSDs less than 8.02%.