Fabrication of a newly lab-made SPME fiber coated with TiO2 nanowire/GO nanocomposite for determination of BTEX from real water samples

Abstract

In this study, a lab-made, low cost and convenient solid phase microextraction (SPME) fiber was successfully fabricated and applied for the simultaneous determination of benzene, toluene, ethylbenzene and xylenes (BTEX) in water samples by headspace (HS) SPME method. The as-made fiber was prepared by coating a stainless steel wire with one of the attractive conformations of TiO2 nanoparticles, namely titanium dioxide nanowire/reduced graphene oxide (TiO2 NWs/RGO). The as-synthesized nanocomposite was characterized with field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) analysis respectively. A Taguchi experimental method with an L16 (45) design was successfully used to optimize the influencing HS-SMPE extraction parameters including extraction time, sample volume, salt effect, heating temperature and pH. Under the optimized conditions, good linearity was observed in the range of 5.0–193.0 ng/mL for all the BTEX compounds, with the correlation coefficients ranging from 0.9901 to 0.9962. The method also demonstrated a high reliability with low limits of detections (LODs) ranging from 5.0 to 11.5 ng/mL and limits of quantification (LOQs) ranging from 16.5 to 34.4 ng/mL, with good repeatability as indicated by RSD% values of less than 12 % (n = 5). The proposed method is simple and rapid, and also provides a much more accurate and sensitive detection platform for the BTEX analysis in real water samples, even by the conventional analytical instruments such as gas chromatography coupled with flame ionization detector. © 2024