Application of magnetic dispersive solid phase extraction combined with solidification of floating organic droplet-based dispersive liquid-liquid microextraction and GC-MS in the extraction and determination of polycyclic aromatic hydrocarbons in honey

A magnetic dispersive solid phase extraction method combined with solidification of floating organic droplet-based dispersive liquid-liquid microextraction has been validated for the extraction of polycyclic aromatic hydrocarbons from honey samples. For this purpose, a carbonised cellulose-ferromagnetic nanocomposite was used as a sorbent through the magnetic dispersive solid phase extraction. For preparation of the sorbent, first, carbonised cellulose nanoparticles were created by treating cellulose filter paper with concentrated solution of sulfuric acid. Then, the prepared nanoparticles were loaded onto Fe3O4 nanoparticles through coprecipitation. In the extraction process, first, a few mg of the sorbent was added to the diluted honey solution and dispersed in it using vortex agitation. The particles were then separated and the adsorbed analytes were eluted with an organic solvent. The eluent was taken and after mixing with a water-immiscible extraction solvent was used in the following solidification of floating organic droplet-based dispersive liquid-liquid microextraction procedure. By performing the extraction process under the obtained optimum conditions, low limits of detection (0.08-0.17 ng g-1) and quantification (0.27-0.57 ng g-1), satisfactory precision (relative standard deviations ≤ 5.0%), and wide linear range (0.57-500 ng g-1) with great coefficients of determination (r2≥ 0.9986) were obtained.

Polycarbonate-coated magnetic nanoparticles for the extraction of imipramine and its primary metabolite from urine

This study introduces a reliable and inexpensive magnetic dispersive solid phase extraction to extract imipramine and its primary metabolite (desipramine) from urine samples. To accomplish this aim, Fe3 O4 magnetic nanoparticles were synthesized by sonication, subsequently, polycarbonate was precipitated gradually onto the surface of them to form the adsorbent. Extraction recoveries of 85% and 76%, enrichment factors of 57 and 51, limits of detection of 2.5 and 2.8 μg/L, and limits of quantification of 8.3 and 9.3 μg/L were obtained for imipramine and desipramine under the optimal conditions, respectively. In addition, relative standard deviations for intra- (n = 6) and inter-day (n = 5) precisions at two concentrations (50 and 100 μg/L of each analyte) were less than or equal to 4%. Short extraction time, good repeatability, high enrichment factors, and simplicity are the main advantages of the proposed method.

Heterogeneous adsorbent based on CeZrO2 nanoparticles doped magnetic graphene oxide used for vortex assisted magnetic dispersive solid phase extraction of erythromycin in chicken

A simple, fast, and efficient method of vortex assisted magnetic dispersive solid phase extraction for separation and pre-concentration of erythromycin in chicken samples prior to high LC-UV determination has been developed. The novel heterogeneous CeZrO₂ nanoparticles doped magnetic graphene oxide, for use as an efficient nanosorbent, was synthetised and applied for the adsorption of erythromycin. The synthetised nanosorbent was characterised using both Fourier-transform infra-red (FT-IR) and energy dispersive X-Ray (EDX) spectroscopy together with field emission scanning electron microscopy-EDX. To obtain the best extraction condition and maximum extraction efficiency of erythromycin, the effect of important parameters including pH, amount of sorbent, vortexing time, ionic strength, sample volume, and desorption conditions were investigated. At optimum conditions, a linear range of 0.25-300 µg kg^-1, LOD (S/N = 3) of 0.079 µg kg^-1, and LOQ (S/N = 10) of 0.270 µg kg^-1 were obtained. The precision of the method was established as having an RSD (%) at 100 µg kg^-1 of erythromycin for seven replicates of 2.6% and 3.2% for the intra-day and the inter-day, respectively. Recoveries over 94.0% confirmed a high capability of the proposed method for separation and determination of erythromycin residues in chicken being one of the most important animal products.

Magnetic dispersive solid phase extraction of some polycyclic aromatic hydrocarbons from honey samples using iron (III) oxinate nanocomposite as an efficient sorbent

In this work, iron (III) oxinate magnetic nanocomposite was synthesized and employed as an efficient sorbent for the magnetic dispersive solid phase extraction of some polycyclic aromatic hydrocarbons from honey samples. In the following, dispersive liquid-liquid microextraction procedure was used to further preconcentration of the analytes. The prepared sorbent was characterized using Fourier transform infrared spectrophotometer, X-ray diffractometer, vibrating sample magnetometer, energy dispersive X-ray spectroscope, and scanning electron microscope. The results verified the successful formation of the magnetic sorbent. In the extraction process, the sorbent was added into an aqueous solution and the mixture was vortexed. After completing the adsorption process, the supernatant phase was separated in the presence of a magnet and the analytes adsorbed onto sorbent were eluted by acetonitrile. Then, μL-level of 1,1,1-trichloroethane was mixed with the obtained acetonitrile and injected into NaCl solution. Finally, one microliter of the sedimented phase was injected into gas chromatography-flame ionization detector after centrifugation. Under the optimum conditions, a great repeatability (relative standard deviation equal or less than 5 and 6% for intra- and inter day precisions, respectively), acceptable extraction recoveries (59-84%), high enrichment factors (118-168), and low limits of detection and quantification (0.16-0.36 and 0.56-1.22 ng g^-1 , respectively) were acquired. This article is protected by copyright. All rights reserved.