Extraction of fluoxetine from aquatic and urine samples using sodium dodecyl sulfate-coated iron oxide magnetic nanoparticles followed by spectrofluorimetric determination

A novel removal of Ni2+ ions from water solutions using dispersive solid-phase extraction method with nano Fe3O4/chitosan-acrylamide hydrogel

The effluent release containing heavy metals as Ni2+ ions has drastic risks to both the natural environment and human health. In this research, the nano Fe3O4/chitosan-acrylamide hydrogel was prepared as a novel nano sorbent for dispersive solid-phase extraction of Ni2+ ions and applied to the water sample solution. The pH, amount and type of elution solvent, the extraction time, etc. were optimized to improve the efficiency of the proposed method. Analytical parameters such as concentration factor and relative standard deviation (%) were achieved as 33.3 and 1.8%, respectively. The capacity in equilibrium sorption was calculated at 22.54 mg g-1. Furthermore, to estimate the adsorption mode, Freundlich, Langmuir, and Temkin models were fitted with experimental isotherm data. Besides, to check the basic process of the metal adsorption mechanism, pseudo-first-order, pseudo-second-order, and Roginsky-Zeldovich models were investigated and the results were fitted with the pseudo-second-order model. The value of change in entropy (⊿S) obtained is -65.24 (J(mol K)-1). Negative values of change in enthalpy, ⊿H in (kJ mol-1) is -24.45 (kJ mol-1) which indicates both physical and chemical adsorptions involved in the process of adsorption. Finally, the nano Fe3O4/chitosan-acrylamide hydrogel exhibited high performance to remove the Ni2+ ions from water sample solution.

Magnetic solid phase extraction of Sunitinib malate in urine samples assisted with mixed hemimicelle and spectrophotometric detection

The mixed hemimicelle-based solid phase extraction method using the coated sodium dodecyl sulfate by magnetic iron oxide nanoparticles as adsorbent was developed for extraction and determination of Sunitinib malate in real samples prior to determination by UV-Visible spectrophotometry. For the characterization of synthesized nanoparticles, Fourier transform infrared spectroscopy, and scanning electron microscopy was used. The influences of different factors affecting the extraction efficiency of Sunitinib malate, including the pH, the adsorbent amount, the volume and eluent type, the amount of the surfactant, the ionic strength, extraction, and desorption time, were investigated. At the optimized conditions, a good linearity with correlation coefficients of 0.998 and 0.999 was obtained over the concentration ranges of 1-22 and 1-19 µg/mL for water and urine samples, in order. The good recoveries of 97% and 99% and also, the limits of detection equal with 0.9, and 0.8 µg/mL for water and urine samples were enhanced, respectively. These results demonstrate that mixed hemimicelle solid phase extraction is a fast, efficient, economical and selective sample preparation method for the extraction and determination of Sunitinib malate in different water and urine sample solutions.

Rapid determination of 2,4-diaminopyrimidine residues through sample pretreatment using immunomagnetic bead purification along with HPLC-UV

To reduce matrix interference and realize simultaneous detection of multiple homologous compounds (trimethoprim (TMP), diaveridine (DVD), ormetoprim (OMP), baquiloprim (BQP), and aditoprim (ADP) in pig, cattle, chicken, and fish muscles), an immunomagnetic bead (IMB)-based sample purification pretreatment with HPLC-UV was developed. A broad-spectrum monoclonal antibody (mAb, named 14C6) was prepared and conjugated with carboxylic-acid-functionalized magnetic nanoparticles using the active ester method to obtain IMBs for sample purification. The extraction solvent was optimized based on the extraction efficiency. Good linearity was observed for all the five analytes (10-200 μg/kg) with the LOD and LOQ of 5 and 10 μg/kg, respectively. The mean recoveries ranged from 62.5% to 76.9%, while the coefficient of variation was <12.2%. The IMB method afforded greater sample purification and enrichment than those achieved with the SPE column-based conventional method. Hence, the IMB-based sample purification is a useful tool to determine 2,4-diaminopyrimidine residues in edible animal tissues.

Magnetic nanobiosorbent (MG-Chi/Fe3 O4 ) for dispersive solid-phase extraction of Cu(II), Pb(II), and Cd(II) followed by flame atomic absorption spectrometry determination

Trace amounts of Cu (II), Pb (II), and Cd (II) in a wastewater sample were preconcentrated with a novel cross‐linked magnetic chitosan modified with a new synthesised methionine‐glutaraldehyde Schiff's base (MG‐Chi/Fe₃O₄) as a dispersive solid‐phase extraction (DSPE) adsorbent. The adsorbed metal ions were then eluted with a specific volume of suitable solution and determined by flame atomic absorption spectrometry (FAAS). Various parameters affecting the extraction efficiency of the metal ions were investigated and optimised, including pH, amount of adsorbent, extraction time, type and volume rate of eluent, elution time, sample volume, and effect of interfering ions. The adsorption kinetics are more consistent with the pseudo‐second order model. The results were statistically interpreted and the analytical performance of the proposed method was found to have preconcentration factors of 55, 60, and 50 μg L⁻¹ for Cu(II), Pb(II), and Cd(II), respectively, limits of detection were 0.22, 0.24, and 0.10 μg L⁻¹ for Cu(II), Pb(II), and Cd(II), respectively, with a relative standard deviation (1.5%‐2.8 %), and the liner range was 5–1000 for Cu(II) and Pb(II) and 2.5–1000 for Cd(II). It was concluded that this method was suitable for successful simultaneous determination of Cu(II), Pb(II), and Cd(II) in industrial wastewater samples.

Hippocampal MicroRNAs Respond to Administration of Antidepressant Fluoxetine in Adult Mice

Current antidepressant treatments to anxiety and depression remain inadequate, burdened by a significant percentage of misuse and drug side-effects, due to unclear mechanisms of actions of antidepressants. To better understand the regulatory roles of antidepressant fluoxetine-related drug reactions, we here investigate changes of expression levels of hippocampal microRNAs (miRNAs) after administration of fluoxetine in normal adult mice. We find that 64 miRNAs showed significant changes between fluoxetine treatment and control groups by analyzing 626 mouse miRNAs. Many miRNAs in response to fluoxetine are involved in neural-related signaling pathways by analyzing miRNA-target gene pairs using the Kyoto encyclopedia of genes and genomes (KEGG) and Gene Ontology (GO). Moreover, miRNAs with altered expression are mainly associated with the repression of the dopaminergic synapse signals, which may affect hippocampal function after fluoxetine treatment. Our results demonstrate that a number of miRNAs respond to antidepressants even in normal mice and may affect target gene expression, which supports the safety consideration of inappropriate treatment and off-label use of antidepressant drugs.

Dispersive admicelle solid-phase extraction based on sodium dodecyl sulfate coated Fe3 O4 nanoparticles for the selective adsorption of three alkaloids in Gegen-Qinlian oral liquid before high-performance liquid chromatography

A novel dispersive admicelle solid-phase extraction method based on sodium dodecyl sulfate-coated Fe₃ O₄ nanoparticles was developed for the selective adsorption of berberine, coptisine, and palmatine in Gegen-Qinlian oral liquid before high-performance liquid chromatography. Fe₃ O₄ nanoparticles were synthesized by a chemical coprecipitation method and characterized by using transmission electron microscopy. Under acidic conditions, the surface of Fe₃ O₄ nanoparticles was coated with sodium dodecyl sulfate to form a nano-sized admicelle magnetic sorbent. Owing to electrostatic interaction, the alkaloids were adsorbed onto the oppositely charged admicelle magnetic nanoparticles. The quick separation of the analyte-adsorbed nanoparticles from the sample solution was performed by using Nd-Fe-B magnet. Best extraction efficiency was achieved under the following conditions: 800 μL Fe₃ O₄ nanoparticles suspension (20 mg/mL), 150 μL sodium dodecyl sulfate solution (10 mg/mL), pH 2, and vortexing time 2 min for the extraction of alkaloids from 10 mL of diluted sample. Four hundred microliters of methanol was used to desorb the alkaloids by vortexing for 1 min. Satisfactory extraction recoveries were obtained in the range of 85.9-120.3%, relative standard deviations for intra- and interday precisions were less than 6.3 and 10.0%, respectively. Finally, the established method was successfully applied to analyze the alkaloids in two batches of Gegen-Qinlian oral liquids.

Review of geometries and coating materials in solid phase microextraction: Opportunities, limitations, and future perspectives

The development of new support and geometries of solid phase microextraction (SPME), including metal fiber assemblies, coated-tip, and thin film microextraction (TFME) (i.e. self-supported, fabric and blade supported), as well as their effects on diffusion and extraction rate of analytes were discussed in the current review. Application of main techniques widely used for preparation of a variety of coating materials of SPME, including sol-gel technique, electrochemical and electrospinning methods as well as the available commercial coatings, were presented. Advantages and limitations of each technique from several aspects, such as range of application, biocompatibility, availability in different geometrical configurations, method of preparation, incorporation of various materials to tune the coating properties, and thermal and physical stability, were also investigated. Future perspectives of each technique to improve the efficiency and stability of the coatings were also summarized. Some interesting materials including ionic liquids (ILs), metal organic frameworks (MOFs) and particle loaded coatings were briefly presented.

Dispersive liquid-liquid microextraction combined with acetonitrile stacking through capillary electrophoresis for the determination of three selective serotonin reuptake inhibitor drugs in body fluids

Dispersive liquid-liquid microextraction was combined with acetonitrile stacking in capillary electrophoresis for the identification of three selective serotonin reuptake inhibitors (citalopram, fluoxetine, and fluvoxamine) in human fluids such as urine and plasma. Parameters that affect the extraction and stacking efficiency, such as the type and volume of the extraction and disperser solvent, extraction time, salt addition for dispersive liquid-liquid microextraction, and sample matrices, pH, and concentration of the separation buffer for stacking, were investigated and optimized. Under optimum conditions, the enrichment factors were in the range of 1195-1441. Limits of detection ranged from 1.4 to 1.7 nM for the target analytes. Calibration graphs displayed satisfied linearity with R² greater than or equal to 0.9978, and relative standard deviations of the peak area analysis were in the range of 2.9-5.0% (n = 3). The recoveries of all tricyclic antidepressant drugs from urine and plasma were in the range of 77-117 and 79-106%, respectively. The findings of this study show that dispersive liquid-liquid microextraction acetonitrile-stacking capillary electrophoresis is a rapid and convenient method for identifying tricyclic antidepressant drugs in urine and plasma.

Polythiophene-Chitosan Magnetic Nanocomposite as a Highly Efficient Medium for Isolation of Fluoxetine from Aqueous and Biological Samples

Polythiophene/chitosan magnetic nanocomposite as an adsorbent of magnetic solid phase extraction was proposed for the isolation of fluoxetine in aqueous and biological samples prior to fluorescence detection at 246 nm. The synthesized nanoparticles, chitosan and polythiophene magnetic nanocomposite, were characterized by scanning electron microscopy, FT-IR, TGA, and EDAX. The separation of the target analyte from the aqueous solution containing the fluoxetine and polythiophene/chitosan magnetic nanocomposite was simply achieved by applying external magnetic field. The main factors affecting the extraction efficiency including desorption conditions, extraction time, ionic strength, and sample solution pH were optimized. The optimum extraction conditions were obtained as 10 min for extraction time, 25 mg for sorbent amount, 50 mL for initial sample volume, methanol as desorption solvent, 1.5 mL for desorption solvent volume, 3 min for desorption time, and being without salt addition. Under the optimum conditions, good linearity was obtained within the range of 15-1000 μg L(-1) for fluoxetine, with correlation coefficients 0.9994. Furthermore, the method was successfully applied to the determination of fluoxetine in urine and human blood plasma samples. Compared with other methods, the current method is characterized with highly easy, fast separation and low detection limits.

Mixed hemimicelles solid-phase extraction of cephalosporins in biological samples with ionic liquid-coated magnetic graphene oxide nanoparticles coupled with high-performance liquid chromatographic analysis

A novel mixed hemimicelles solid phase extraction based on magnetic graphene oxide (Fe3O4/GO) and ionic liquid (IL) was developed for the simultaneous extraction and determination of trace cephalosporins in spiked human urine. The high surface area and excellent adsorption capacity of the graphene oxide after modification with1-hexadecyl-3-methylmidazoliumbromide(C16mimBr) were utilized adequately in the solid phase extraction(SPE) process. A comprehensive study of the parameters affecting the extraction recovery, such as the zeta-potential of magnetic graphene oxide, amounts of magnetic graphene oxide and surfactant, pH of solution, ionic strength, extraction time, and desorption condition were optimized. A comparative study on the use of different surfacant-coated Fe3O4/GO NPs as sorbents was presented. Good linearity (R(2)>0.9987) for all calibration curves was obtained. The LODs were ranged between 0.6 and 1.9ng mL(-1) for the cephalosporins and the LOQs were 1.5 to 5.5, respectively. Satisfactory recoveries(84.3% to 101.7%)and low relative standard deviations from 1.7% to 6.3% in biological matrices were achieved. The mixed hemimicelles magnetic SPE (MSPE) method based on ILs and Fe3O4/GO NPs magnetic separation has ever been successfully used for pretreatment of complex biological samples.

Silane modified magnetic nanoparticles as a novel adsorbent for determination of morphine at trace levels in human hair samples by high-performance liquid chromatography with diode array detection

In this paper we report a novel, sensitive, and rapid method of magnetic solid phase extraction based on surface modified magnetic nanoparticles as a novel nano sorbent for HPLC determination of morphine with diode array detection in human hair samples. Factors affecting the extraction efficiency of the proposed method, including the sample pH, quantity of magnetic nanoparticles, sample volume, desorption solvent type and its volume, and extraction time were investigated and optimized. Under the optimized experimental conditions, a good linearity was observed in the range of 1-800 µgL(-1) for the morphine, with a correlation coefficient (R (2)) of 0.990. The pre-concentration factor of 208.69 was achieved in this method. The detection limit of the method was 0.1 μgL(-1) based on S/N = 3 and good reproducibility with a relative standard deviations lower than (n = 5) 2.59 %. The proposed method has been successfully applied to the analysis of trace amounts of morphine in human hair samples with satisfactory results. This method can be applied in medical toxicology research and forensic medical centers.

Magnetized silane-coupling agent KH-570 based solid-phase extraction followed by gas chromatography-flame ionization detection to determine venlafaxine in human hair and aqueous environmental samples

In the present study, a novel adsorbent, Fe3O4 magnetic nanoparticles (MNPs) functionalized by silane-coupling agent KH-570, was successfully synthesized. The prepared MNPs were characterized by Fourier-transform infrared spectroscopy and transmission electron microscopy. It was applied as functionalized magnetic nano-adsorbent for magnetic solid-phase extraction of trace levels of venlafaxine using gas chromatography with flame ionization detector. This method was developed and optimized for use in analysis of venlafaxine in human hair and aqueous environmental samples. The main factors influencing the extraction efficiency including pH of sample, amount of the MNPs, adsorption time, volume of sample, and desorption conditions such as volume of solvent and desorption time were studied and optimized. Under the optimized experimental conditions, good linearity was observed in the range of 1-1,000 µg L(-1) for aqueous environmental samples with correlation coefficients (R (2)) 0.996. The limits of detection and quantification were 0.1 and 0.5 μg L(-1), respectively. Good reproducibility with the relative standard deviations (n = 5) 3.21 % was obtained. The developed method was successfully applied to the extraction of venlafaxine from spiked human hair, river water, and surface water samples and the relative recoveries of 89.36, 93.43, and 94.99 % were obtained, respectively. The results indicated that Fe3O4/KH-570 MNPs have a satisfying extraction efficiency and can be served as a sensitive, inexpensive, and reliable method for analysis of antidepressant drugs such as venlafaxine in biological and aqueous environmental samples.

On-line microextraction of moxifloxacin using Fe3O4 nanoparticle-packed in-tube SPME

An in-tube SPME based on the use of a Fe₃O₄ nanoparticles-packed tube has been reported.

Magnetic solid phase extraction of mefenamic acid from biological samples based on the formation of mixed hemimicelle aggregates on Fe(3)O(4) nanoparticles prior to its HPLC-UV detection

A novel and sensitive solid phase extraction method based on the adsorption of cetyltrimethylammonium bromide on the surface of Fe3O4 nanoparticles was developed for extraction and preconcentration of ultra-trace amounts of mefenamic acid in biological fluids. The remarkable properties of Fe3O4 nanoparticles including high surface area and strong magnetization were utilized in this SPE procedure so that a high enrichment factor (98) and satisfactory extraction recoveries (92-99%) were obtained using only 50mg of magnetic adsorbent. Furthermore, a fast separation time (about 15min) was achieved for a large sample volume (200mL) avoiding time-consuming column-passing process of conventional SPE. A comprehensive study on the parameters effecting the extraction recovery such of the amount of surfactant, pH value, the amount of Fe3O4 nanoparticles, sample volume, desorption conditions and ionic strength were also presented. Under the optimum conditions, the method was linear in the 0.2-200ngmL(-1) range and good linearity (r(2)>0.9991) was obtained for all calibration curves. The limit of detection was 0.097 and 0.087ngmL(-1) in plasma and urine samples, respectively. The relative standard deviation (RSD %) for 10 and 50ngmL(-1) of the analyte (n=5) were 1.6% and 2.1% in plasma and 1.2% and 1.9% in urine samples, respectively. Finally, the method was successfully applied to the extraction and preconcentration of mefenamic acid in human plasma and urine samples.