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A procedure is reported for the efficient extraction and determination of phenolics from aqueous media. The approach is based on the dispersive micro-solid phase extraction using synthesized Co3O4 nanocube-functionalized nitrogen-doped melamine foam. The adsorption and desorption conditions were optimized by response surface methodology and one-variable-at-a-time approaches. The proposed method was fully validated. Under the optimized conditions, the limits of detection were lower than 0.5 ng mL−1. Calibration curves were linear in the range from 1.0 to 250.0 ng mL−1, 0.7 to 200.0 ng mL−1, 0.2 to 250.0 ng mL−1, and 1.0 to 250.0 ng mL−1 for phenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, and pentachlorophenol, respectively. Enrichment factors and absolute recoveries from 17.5 to 20.7 and 70% to 83% were achieved. The method was successfully applied for trace monitoring of the analytes in environmental and industrial water samples with gas chromatography—flame ionization detection analysis. Satisfactory relative recoveries between 89.0% and 105.8% were obtained along with acceptable precision below 8.1%. This method is a simple, rapid, sensitive, and reliable protocol for efficient screening of the phenolics. [ABSTRACT FROM AUTHOR]

A modified Co3O4 nanocube-coated melamine-derived carbon sponge was synthesized and implemented for an in-syringe micro-solid-phase extraction approach as a promising sorbent. The introduced method combined with gas chromatography–flame ionization detection has been successfully developed for the determination of naphthalene, anthracene, and pyrene in environmental water samples. Significant adsorption and desorption parameters, including sorbent amount (19.0 mg), sample pH (7.4) and flow rate (233.0 µL min−1), salt concentration (20.0%), number of adsorption (4) and desorption (4) cycles, eluent volume (425.0 µL) and its flow rate (153.0 µL min−1), were optimized by the central composite design. Under the optimal conditions, the calibration curves were linear in the range of 3.0–500.0, 1.0–250.0, and 0.8–250.0 ng mL−1 for naphthalene, anthracene, and pyrene, respectively, along with acceptable intra- and inter-day precision (≤ 8.3%). The absolute recoveries were obtained in the range of 57.4–76.6%, while limits of detection were found between 0.2 and 0.8 ng mL−1. Eventually, the proposed method was successfully applied for the determination of the studied compounds in environmental and industrial water samples with satisfactory relative recoveries between 87.5 and 104.5%. The approach minimizes organic solvent consumption, sorbent amount, and sample solution volume, resulting in reasonable sensitivity and excellent reusability. This quantitative protocol is an efficient and satisfactory analytical procedure because of its high accuracy and precision. It proved to be highly cost-effective and reliable for screening purposes. [ABSTRACT FROM AUTHOR]

In this study, heavy metals pollutions in waters, soils and vegetables were investigated from farms, near oil refinery in south of Tehran city, Iran (Shahre Ray). The most important heavy metals in Iranian oil are vanadium, cobalt, nickel, arsenic and mercury (V, Co, Ni, As, Hg). In this region, the concentration of heavy metals in soils, well waters and leafy edible vegetables were evaluated in ten different points of farms. Geographic information systems (GIS) were used to estimate the levels of heavy metals concentration at unmeasured locations. After sample preparation, concentrations of heavy metals in vegetables, soils and waters were determined by atomic absorption spectrometry (AAS). Five different leafy edible vegetables from farms, i.e., Persian leek, dill, parsley, spinach and radish were sampled in spring, summer and autumn 2012. In vegetables and well water samples, the concentrations of V, Ni and Co were above the permissible limit of heavy metals as compared to WHO guidelines and the concentrations of these metals in agricultural soils were found to be lower in accordance to soil references. The industrial waste waters had high concentration of heavy metals in this area. In consequence, the results of this study indicate that industrial waste water can cause pollution in well waters and edible vegetables. So, this region is not suitable for cultivation and growing vegetables.

Background and Aim: Lifestyle changes are associated with an increased incidence of stroke especially in young adults. The purpose of this study was to investigate the lifestyle of ischemic stroke cases under the age of 50 years. Methods: This descriptive cross-sectional study was conducted on young adults with ischemic stroke who were admitted to some hospitals, Tehran, Iran between 2018 and 2019. Total lifestyle information collected in the form then was compared in males and females. Results: Totally 11% ischemic stroke was under age 50 years. 60.7% of young adult patients were men. There was significant difference between body mass index (BMI) (P = 0.03), type of job (P = 0.04), physical activity (P = 0.02), fruit and vegetables consumption, and gender of patients (P = 0.02). Conclusion: According to the association between inappropriate lifestyle and ischemic stroke in young adults, it is recommended to set preventive medicine and health promotion units with insurance coverage in all clinics for risk assessment of stroke in healthy general population specialty young adults. [ABSTRACT FROM AUTHOR]

A simple and efficient ionic liquid-based ultrasound-assisted in-situ solvent formation microextraction (IL-UA-ISFME) in combination with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) has been gainfully developed for the trace determination of four phthalate esters (PEs) in environmental water samples. In this method, a hydrophobic ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) was created by addition of a hydrophilic ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate) to sample solution constituting an ionpairing agent (NaPF6). The analytes were extracted inside the ionic liquid phase while the microextraction solvent was dispersed through the sample by utilizing ultrasonic radiation. The sample was then centrifuged and extracting phase retracted into the microsyringe, diluted with acetonitrile, and injected to HPLC. At first, vigorous parameters controlling the performance of the microextraction process were considered and optimized. The limit of detections (LOD, S/N = 3) were in the range of 0.22-0.33 µg L-1 while the RSD% values were below than 6.1% (n = 5). A good linearity (0.996 = r2 = 0.992) and a broad linear over the concentration range from 1.0 to 500 µg L-1 were achieved. At last, the method was applied for the preconcentration and sensitive determination of the PEs in several environmental water samples. The accuracy of the method in the real samples was examined by the relative recovery experiments with results ranging from 90-107%, which approved that intricate matrixes had approximately slight effect on the developed procedure. [ABSTRACT FROM AUTHOR]

A novel and efficient hollow fiber-based method, viz. magnetic solvent bar liquid-phase microextraction (MSB-LPME) combined with gas chromatography-flame ionization detection (GC-FID) was successfully developed for the trace determination of selected polycyclic aromatic hydrocarbons (PAHs) in environmental water samples. The target analytes were extracted from sample solution to the organic solvent immobilized in a fiber. After extraction, the analyte-adsorbed magnetic solvent bar could be readily isolated from the sample solution by a magnet which could greatly simplify the operation and also decline the total pretreatment time. The bar was first eluted with methanol, evaporated to dryness while the residue was dissolved in toluene and finally injected into GC-FID. Begin with, effective parameters controlling the performance of the microextraction were evaluated and optimized. The values of the detection limit of the method were in the range of 0.05-0.08 μg L-1 and the RSD% values for the analysis of 10.0 μg L-1 of the analytes was below than 5.8% (n= 6). A good linearity (0.998 ≥ r² ≥ 0.994) and a broad linear range (0.1-200 μg L-1) were obtained. The method was eventually utilized for the preconcentration and determination of the PAHs in environmental water samples and satisfactory results were obtained. [ABSTRACT FROM AUTHOR]

Herein, an efficient graphene oxide/FeO@polythionine (GO/FeO/PTh) nanocomposite sorbent was introduced for magnetic solid-phase extraction combined with high-performance liquid chromatography-ultraviolet detection of duloxetine (DLX) in human plasma. To prepare the sorbent, an oxidative polymerization of thionine on the surface of magnetic GO was utilized while PTh was simply used as a surface modifier to improve extraction efficiency. Transmission electron microscopy, scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray analysis, vibrating sample magnetometry, Fourier transform-infrared spectroscopy and Brunauer-Emmett-Teller technique were applied to characterize the prepared nanoparticles. Firstly, effective parameters controlling the performance of the extraction process were evaluated in detail and optimized. Under the optimized conditions, calibration curve showed linearity in the range of 2-2500 ng mL with regression coefficient corresponding to 0.998. Limits of detection (LOD, S/N = 3) and quantification (LOQ, S/N = 10) were 0.5 and 2 ng mL, respectively. Reasonable intra-assay (3.5-4.5%, n = 6) and inter-assay (3.8-6.7%, n = 9) precision represented acceptable performance of the procedure. The applicability of the method was successfully extended to the determination of DLX in human plasma after oral administration of 60 mg single dose of the drug and finally some pharmacokinetic data was achieved. [ABSTRACT FROM AUTHOR]