evaluating the effect of magnetic field in magnetic fiber headspace solid-phase microextraction of volatile components using fe3o4@mcm-41/ mil-101 (fe)/ mil-53 (fe) nanocomposite

Solid-phase microextraction (spme), a relatively efficient and versatile sample preparation method, was developed by pawliszyn. the fiber-based spme is simple, rapid, solvent free and cost effective [1]. to improve the capabilities and expand the applications of this technique, different configurations of spme have been developed and promoted during the recent years. in addition, reinforced spme techniques such as vortex-assisted [2], microwave-assisted [3] and solvent-assisted [4] techniques have been emerged recently. in this work, a technique has been developed for magnetic fiber headspace-solid phase microextraction (mf-hs-spme) of plant volatile components. for this purpose, fe3o4@mcm-41 (mobil composition of matter no. 41; a nanoporous sorbent) /the porous mil-101(fe) metal–organic framework/ mil-53 (fe) nanocomposite was prepared and used as the fiber coating. the resulting material was characterized by sem, xrd, bet, tga and ftir. the extraction efficiency for the components of nepeta elymaitica bornm (one of the endemic species in the genus nepeta in iran) was compared with different systems. comparison of permanent magnets and ac and dc magnetic fields indicated the superior effect of the ac field for the target analytes. optimization of the extraction parameters including extraction temperature, extraction time, moisture content of the sample, desorption time and desorption temperature was carried out using a gc-ms instrument and a simplex method. the prepared fiber was stable in multiple injections with relative standard deviations of 5.3 to 10.9% for 6 replicates. the proposed method was successfully applied to the extraction and identification of volatile components of some nepeta elymaitica bornm samples. according to the results obtained by gc-fid, 1,8-cineol, nepetalactone (4a-α,7- α,,7a- α), e-caryophyllene, terpiene-4-ol and linalool were the main components of the plant.