Metal organic framework MIL-101 coated fiber for headspace solid phase microextraction of volatile aromatic compounds

Abstract

A sol–gel coating technique was applied for the preparation of metal organic frameworks (MOFs)-based solid phase microextraction (SPME) fibers by coating MIL-101 onto stainless steel wires. The prepared fiber was explored for the headspace SPME (HS-SPME) of seven volatile aromatic compounds (VACs) from water samples followed by gas chromatography-mass spectrometric analysis. Several important experimental parameters, such as extraction temperature, extraction time, sample volume, salt addition and desorption conditions, were investigated. Under the optimized experimental conditions, the developed HS-SPME method with MIL-101 coated fiber had a good linearity in the range of 0.05–50.0 μg L⁻¹ for the analytes with the correlation coefficients (r) ranging from 0.9974 to 0.9988. Based on a signal-to-noise ratio (S/N) of 3, the limits of detection (LODs) for the seven analytes ranged from 1.0 to 5.0 ng L⁻¹. Compared with two commercial SPME fibers, the laboratory-made MIL-101 coated fiber showed a higher extraction efficiency for the seven VACs. The established method was successfully applied for the determination of the VACs in real local tap and lake water samples. The recoveries for the method of the seven VACs at spiking levels of 0.1 and 5.0 μg L⁻¹ were in the range from 76.4% to 116.1%.