Zeolite imidazolate framework nanocrystals electrodeposited on stainless steel fiber for determination of polycyclic aromatic hydrocarbons

Abstract

New solid phase microextraction (SPME) coating was made by electrodeposition of zeolite imidazolate framework (ZIF-67) nanocrystals with the aid of polyaniline (PANI) on steel fiber. The SPME fiber was used to extract four polycyclic aromatic hydrocarbons (PAHs) from headspace (HS) of tea infusions and determined by gas chromatography coupled with flame ionization detector (GC-FID). The coating of the SPME fiber was characterized by Fourier transformed infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Vital parameters affecting extraction performance, including desorption conditions, salt concentration, extraction time, and temperature, have been evaluated and optimized. The validated method was specific for the PAHs analysis, with the limit of detection (LOD) as low as 20.0 to 50.0 ng/L. The linear range was relevant to 70.0-180.0 ng/L with relative standard deviation (RSD) % of less than 12.8. The factor of enrichment was found to be 446.7-808.8. The synthesized coating was shown to be thermally and chemically stable. The recommended approach was successfully applied to quantify PAHs in some frequent tea infusions in the market. The fiber coating of ZIF-67 can be easily made and applied efficiently to detect PAHs pollution in the environment and food products.