High-throughput method based on a novel thin-film microextraction coating for determining macrolides and lincosamides in honey

New Materials for Thin-Film Solid-Phase Microextraction (TF-SPME) and Their Use for Isolation and Preconcentration of Selected Compounds from Aqueous, Biological and Food Matrices

Determination of a broad spectrum of analytes, carried out with analytical instruments in samples with complex matrices, including environmental, biological, and food samples, involves the development of new and selective sorption phases used in microextraction techniques that allow their isolation from the matrix. SPME solid-phase microextraction is compatible with green analytical chemistry among the sample preparation techniques, as it reduces the use of toxic organic solvents to the minimum necessary. Over the past two decades, it has undergone impressive progress, resulting in the development of the thin-film solid-phase microextraction technique, TF-SPME (the thin-film solid-phase microextraction), which is characterized by a much larger surface area of the sorption phase compared to that of the SPME fiber. TF-SPME devices, in the form of a mostly rectangular metal or polymer substrate onto which a thin film of sorption phase is applied, are characterized, among others, by a higher sorption capacity. In comparison with microextraction carried out on SPME fiber, they enable faster microextraction of analytes. The active phase on which analyte sorption occurs can be applied to the substrate through techniques such as dip coating, spin coating, electrospinning, rod coating, and spray coating. The dynamic development of materials chemistry makes it possible to use increasingly advanced materials as selective sorption phases in the TF-SPME technique: polymers, conducting polymers, molecularly imprinted polymers, organometallic frameworks, carbon nanomaterials, aptamers, polymeric ionic liquids, and deep eutectic solvents. Therefore, TF-SPME has been successfully used to prepare analytical samples to determine a broad spectrum of analytes in sample matrices: environmental, biological, and food. The work will be a review of the above-mentioned issues.

A Lincomycin-Specific Antibody Was Developed Using Hapten Prediction, and an Immunoassay Was Established to Detect Lincomycin in Pork and Milk

Prolonged consumption of animal-derived foods containing high levels of lincomycin (LIN) residues can adversely impact human health. Therefore, it is essential to develop specific antibodies and immunoassay methods for LIN. This study utilized computational chemistry to predict the efficacy of LIN haptens prior to chemical synthesis, with subsequent confirmation obtained through an immunization experiment. A hybridoma cell line named LIN/1B11 was established, which is specific to LIN. The optimized indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) method exhibited high specificity for detecting LIN residues, with an IC50 value of 0.57 ± 0.03 µg/kg. The method effectively detected LIN residues in pork and milk samples, achieving a limit of detection (LOD) ranging from 0.81 to 1.20 µg/kg and a limit of quantification (LOQ) ranging from 2.09 to 2.29 µg/kg, with recovery rates between 81.9% and 108.8%. This study offers a valuable tool for identifying LIN residues in animal-derived food products. Furthermore, the efficient hapten prediction method presented herein improves antibody preparation efficiency and provides a simple method for researchers in screening haptens.

A configuration for cooling assisted organic solvent coated thin film microextraction after dispersive liquid-liquid microextraction method: A microextraction method for ultra-trace analyzing of volatile sample

A combination of the dispersive liquid-liquid microextraction (DLLME) method based on the total vaporization procedure and cooling-assisted organic solvent-coated thin film microextraction (TFME) was applied for extracting chlorpyrifos (as the model compound). Based on the high thermal conductivity, a nickel foam thin film with the dimensions of 5.0 mm × 5.0 mm was used as a substrate for holding the organic solvent. Supporting thin film by organic solvent increases the thickness and contact area of the film relative to TFME or single drop microextraction (SDME) alone, resulting in a dramatic increase in the extraction efficiency. To protect the organic solvent and enhance the analyte distribution coefficient between the film and the vapor phase, a cooling system was applied. The proposed design was effective due to condensing the target analyte only on the uniform cooled thin film and not on the other regions in the extraction chamber. A corona discharge ionization source-ion mobility spectrometer was employed to identify the analyte. After optimizing the effective parameters, the limits of quantification (S/N = 10) and detection (S/N = 3) were calculated 0.1 and 0.03 μg L-1, respectively, and the dynamic range was measured between 0.1 and 7.0 μg L-1, with a determination coefficient of 0.9997. For three concentration levels of 0.1, 3.0, and 7.0 μg L-1, the relative standard deviations (n = 3) as the repeatability index were to be 6 %, 5 %, and 4 % for intra-day and 9 %, 6 %, and 5 % for inter-day, respectively. The enrichment factor was also calculated to be 3630 for the analyte concentration of 1.0 μg L-1. Well water, potato, and agricultural wastewater were analyzed as the real samples and the relative recovery values were measured between 92 % and 99 %. The accuracy of the proposed technique was validated by the European Standards EN 12393 method. In this approach, two steps of analyte extraction (DLLME and TFME) were used consecutively, resulting in better preconcentration and reduced matrix interference during cleaning-up.

Hybrid porous material supported in a cellulose acetate polymeric membrane for the direct immersion thin-film microextraction of parabens in water

A simple and sensitive direct immersion thin-film microextraction (DI-TFME) method based on MIL-101(Cr) modified with carbon nanofibers supported in cellulose acetate (CA-MIL-101(Cr)@CNFs) polymeric membrane was developed for the extraction and preconcentration of parabens in environmental water samples. A high-performance liquid chromatography-diode array detector (HPLC-DAD) was used for the determination and quantification of methylparaben (MP) and propylparaben (PP). The factors affecting the DI-TFME performance were investigated using central composite design (CCD). The linearity of the DI-TFME/HPLC-DAD method obtained under optimal conditions was 0.04-0.04-500 µg/L with a correlation coefficient (R2) greater than 0.99, respectively. The limits of detection (LOD) and quantification (LOQ) for methylparaben were 11 ng/L and 37 ng/L; for propylparaben, they were 13 ng/L and 43 ng/L, respectively. The enrichment factors were 93.7 and 123 for methylparaben and propylparaben. The intraday (repeatability) and interday (reproducibility) precisions expressed as relative standard deviations (%RSD) were less than 5%. Furthermore, the DI-TFME/HPLC-DAD method was validated using real water samples spiked with known concentrations of the analytes. The recoveries ranged from 91.5 to 99.8%, and intraday and interday trueness values were less than ±15%. The DI-TFME/HPLC-DAD approach was effectively used for the preconcentration and quantification of parabens in river water and wastewater samples.

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.

A magnetic solid phase extraction based on UiO-67@GO@Fe3O4 coupled with UPLC-MS/MS for the determination of nitroimidazoles and benzimidazoles in honey

A novel composite material consisting of zirconiumbiphenyldicarboxylate metal-organic framework, graphite oxide and ferroferric oxide was fabricated by a facile one-step method and served as a magnetic solid phase extraction sorbent for the simultaneous determination of nitroimidazoles and benzimidazoles in honey. The amount of graphite oxide for the synthesis of composite material and analysis parameters were optimized. The optimum parameters were: dipotassium hydrogen phosphate buffer solution (pH 6) as diluent solvent, adsorption time 10 min, desorption time 5 min, methanol/acetonitrile (1:1, V/V) as desorption solvent. The targets were detected by ultra-high performance liquid chromatography tandem mass spectrometry. The recoveries of twelve analytes ranged in 70.5%-103.4% with relative standard deviations lower than 12.9% (n = 3). The quantification limits were 0.2-0.6 μg/kg. Using the composite material as sorbent, a simple, rapid and environmental-friendly method based on magnetic solid phase extraction was successfully developed for determination of seven nitroimidazoles and five benzimidazoles in honey.

Template-directed synthesis of zeolitic imidazolate framework-8 derived Zn-Al layered double oxides decorated on the electrochemically anodized nanoporous aluminum substrate for thin film microextraction of chlorophenols followed by determination with high-performance liquid chromatography

In this work, hierarchical ZIF-8 coated anodized aluminum foil was prepared through in situ template-directed method without addition of any zinc salt. The hierarchical sorbent was synthesized by the formation of the final HZIF-8 on the previously created layered double oxide (LDO) template. The LDO template was created by calcining the firstly in situ prepared desired layered double hydroxide (LDH) precursor coated on the electrochemically anodized porous Al foil in an air atmosphere. The microextraction ability of the extracting device was studied through direct immersion thin film microextraction (DI-TFME). The extracted analytes were quantified by high-performance liquid chromatography equipped by UV detector (HPLC-UV). The present strategy was used for the simultaneous extraction and quantification of four selected chlorophenols (CPs) (as model analyte). The variables of the TFME were optimized using response surface methodology (Plackett-Burman and Box-Behnken design). Under the obtained optimum condition, the prepared film presented acceptable extraction properties including low limits of detection (0.03-0.22 µgL^-1), good linear ranges (0.2-200 µgL^-1, r² > 0.9918) and satisfactory reproducibility (relative standard deviation, 3.6 < RSD < 5.8% for one film as inter- and intra-day RSD, 4.8 < RSD < 5.3% for film to film). Moreover, the obtained enrichment factors were in the range of 56-76. The kinetics and adsorption isotherm of the selected analytes adsorption to the prepared sorbent were also investigated. The maximum adsorption capacities of the selected analytes on the prepared sorbent were in the range of 26.4-80.1 mg g^-1. The adsorption isotherm obeyed the Langmuir and Freundlich models. Moreover, the adsorption of the selected chlorophenols on the prepared film followed the pseudo-second-order kinetic model. Finally, the HZIF-8 film was utilized for the quantification of selected CPs in different types of water and wastewater samples. The results showed satisfactory relative recoveries (93-102%) and acceptable precisions (3.6 < RSD < 9.2%).