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In present work, a sample pre-treatment method based on a combination of homogenous liquid–liquid extraction and dispersive liquid–liquid microextraction has been proposed for the extraction of some organochlorine pesticide residues in cocoa powder before their quantification by gas chromatography–electron capture detection. To extract the analytes, a mixture of acetonitrile and potassium hydroxide solution is added to cocoa powder. In the following, an appropriate amount of sodium chloride as a phase separation agent is added and the mixture is vortexed. After centrifugation, the supernatant phase (acetonitrile containing the extracted analytes) is separated and mixed with chloroform (as an extraction solvent). This mixture is rapidly injected into the deionised water which its pH is 6.4. By this action, a cloudy solution is obtained and after centrifugation, an aliquat of the sedimented phase is removed and injected into the quantification system. Under optimum conditions, limits of detection and quantification of the analytes were found to be in the ranges of 0.024–0.041 and 0.081–0.138 ng g–1, respectively. The obtained extraction recoveries varied between 50 and 89%. Also, intra – (n = 6) and inter–day (n = 4) precisions, experiments as relative standards deviations were less than 8.9% for the studied pesticides at different concentrations (0.2, 1.0, 100 and 250 ng g−1, each analyte). Finally, the suggested method was applied to determine the studied organochlorine pesticide residues in various cocoa powders gathered from groceries in the East Azerbaijan Province, Iran. Abbreviations: DLLME, Dispersive liquid–liquid microextraction; ECD, Electron capture detector; ER, Extraction recovery; EF, Enrichment factor; GC, Gas chromatography; HLLE, Homogenous liquid–liquid extraction; LOD, Limit of detection; LOQ, Limit of quantification; LR, Linear range; RSD, Relative standard deviation; OCP, Organochlorine pesticide [ABSTRACT FROM AUTHOR]

This study aimed to determine the concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) using salting-out assisted liquid–liquid extraction (SALLE) in influent and effluent of Ahvaz water treatment plants during 2018–2019. All measured concentrations were less than the maximum allowable concentrations recommended by the National Standards Organization of Iran (1053) and WHO guidelines. The results showed that the Ahvaz treatment plant decreased the concentration of 2,4-D by 69.2%. Therefore, it is necessary to measure the persistent organic pollutants such as pesticides in different seasons, especially in autumn, winter, and spring that the chemical fertilizers and pesticides are commonly used. [ABSTRACT FROM AUTHOR]

A temperature‐induced counter‐current homogenous liquid‐liquid extraction procedure performed in a burette has been proposed for the isolation of aflatoxins B1, B2, G1, and G2 from various fruit chip samples. In this method, a homogenous solution of deionized water and cyclohexylamine is added to the solid sample and the resulted mixture is vortexed. In the following, the liquid phase is taken and passed through the burette filled with a mixture of calcium oxide (as a phase separation agent) and sand (to avoid clumping the calcium oxide). By doing so, the temperature of the solution is increased by hydration of calcium oxide and consequently, the homogenous state is broken and the aflatoxins are migrated into the resulted tiny droplets of cyclohexylamine. This phase is collected on the top of the solution owing to its low density with respect to an aqueous solution. Numerous parameters which can affect the efficiency of the suggested approach were evaluated and under the best situations, great repeatability, low limits of determination and quantification, and high extraction recoveries were acquired. In the end, the suggested approach was employed for the quantification of the selected aflatoxins in various fruit chips samples marketed in Tabriz City, Iran. [ABSTRACT FROM AUTHOR]

In this work, a homogenous liquid–liquid extraction method was combined with dispersive liquid–liquid microextraction and utilized for the extraction of Co, Zn, Ni, Cu, Pb, and Tl from honey samples before their determination by inductively coupled plasma-atomic emission spectrometry. For this purpose, firstly, diluted honey solution was transferred into a glass test tube and mixed with a few milliliters of a mixture of n -butanol and choline chloride: menthol: p -aminophenol deep eutectic solvent. A homogenous solution was obtained. After that an appropriate amount of sodium chloride was added into the solution and sonicated for 6 min. During this step, the homogenous solution was broken and the mixture of n -butanol and the deep eutectic solvent mixture was collected on top of the solution. The supernatant phase was removed and quickly injected into deionized water. After centrifugation, the collected phase at the bottom of the tube was injected into the determination system. Under the optimum situations, low limits of detection (0.24–0.74 ng g–1) and quantification (0.79–2.46 ng g–1), high extraction recoveries (80–92%), and good repeatability (relative standard deviations equal to or less than 3.6% and 3.9% for intra– and inter-day precisions, respectively) were acquired. Finally, the offered method was employed for determination of the studied heavy metals in various honey samples marketed in Tabriz city, Iran. • A green three-component DES was used as an extraction solvent and complexing agent. • SIHLLE combined with DLLME was used for extraction of heavy metals. • ICP-AES method was used for determination of the analytes. • Greenness, low cost, and effective sample preparation are advantages of the method. [ABSTRACT FROM AUTHOR]

Agricultural development is inevitable to meet the growing need for food. But along with this development, there are unintended and undesirable consequences for human life and the environment that need, found a solution and corrected. One of the most important adverse consequences of agricultural development is the pollution of surface and groundwater resources, which results from various factors such as soil erosion and improper use of different pesticides. This study aimed to conduct an environmental monitoring program in Naseri wetland to determine the concentrations of organophosphorus pesticides (OPP s) in water samples and also to evaluate the potential risks (ecological and health risk assessment) of these pesticides. The salting-out assisted liquid-liquid extraction method was used to extract pesticides. The residual concentrations of OPP s evaluated by gas chromatography/mass spectrometry (GC/MS). In this study, the ecological risk of OPP s calculated for wetland ecosystem, based on the acute risk quotient (RQ i) formula with maximum (RQ max), mean (RQ mean), and mixture (RQ mix) concentrations of organophosphorus pesticides in the wetland water. Also, to assess the health risk of consuming contaminated fish with organophosphate pesticides, the potential non-carcinogenic and carcinogenic risks were determined by the hazard quotient (Index) (HQ, HI) and incremental lifetime cancer risk (ILCR) indices, respectively. The mean ± SD concentration of OPP s (Chlorpyrifos, Malathion, Ethion, Dichlorvos, Trifluralin and Diazinon) in samples of wetland water ranged from 0.14 ± 0.08 to 0.35 ± 0.12 and 0.054 ± 0.06 to 0.2 ± 0.1 (μg/L) in summer and autumn, respectively. The mean ± SD of OPP s in fish varied from 0.68 ± 0.86 to 3.94 ± 2.7 (μg/kg). Overall, the concentrations of pesticides in all water and fish samples were below the maximum residue limit (30 μg/kg) during the study period, according to the Environmental Protection Agency (EPA) and the World Health Organization (WHO). The results of acute risk quotient were in summer (RQ max = 3.49E-4 to 0.067, RQ mean = 5.8E-5 to 0.029, RQ mix = 0.139 - 0.026, 0.018 - 3.42E-3) and autumn (RQ max = 8E-4 to 0.051, RQ mean = 7.74E-6 to 0.018 RQ mix = 0.1 – 0.013, 6E-3- 1.5E-3). The non-carcinogenic and carcinogenic risk indexes due to fish consumption for adults and children were (HQ = 0.026 - 4.68E-4, HI = 0.041, ILCR = 1.7E-7) and (HQ = 1.85E-3-1.3E-5, HI = 0.041, ILCR = 5.55E-8), respectively. The risk of OPP s was generally low. But cumulative risk (pesticide mixtures), should not be ignored. [Display omitted] • Organophosphate pesticide residues measured in water and the muscle tissue of fish (Cyprinus carpio) of the Naseri artificial wetland. • The highest mean concentration of pesticides in fish tissue was related to Trifluralin • The increase of OPP s pollution in the northern areas of the wetland was due to the electrical conductivity (EC) and pH of the wetland water in summer and autumn. • OPP s showed low risk (RQ < 0.01, 0.01 ≤ RQ ≤ 0.1) based on the scenario RQ max and RQ mean for aquatic species. • The highest impact of cumulative risk (RQ mix) of OPP s on wetland species was related to Malathion and Chlorpyrifos. • The risk of carcinogenicity (CR <1E-6) and non-carcinogenicity (HQ, HI <1) of OPPs was within the safe range for children and adults. However, some considerations needed for children [ABSTRACT FROM AUTHOR]

In this study, a combination of homogeneous liquid-liquid extraction and dispersive liquid-liquid microextraction based on solidification of a deep eutectic solvent has been utilized as an efficient method for the extraction of three widely used antibiotics (oxytetracycline, penicillin G, and tilmicosin) from sausage samples. In this method, initially the antibiotics are extracted from the powdered sausage sample into acetonitrile and then, to concentrate the analytes and achieve a high sensitivity, the obtained acetonitrile is mixed with an extraction solvent (a newly synthesized water-immiscible deep eutectic solvent with a melting point near room temperature), and the obtained mixture is rapidly injected into deionized water. In the next step, the mixture is transferred into an ice bath and the solidified extraction solvent containing the analytes is removed and dissolved in ACN. For quantitative analysis, this phase is taken and injected into an ion mobility spectrometer which operated in the positive mode and is equipped with a continuous corona discharge ionizer. This instrumental technique characterizes molecules based on the gaseous phase mobility of their ions formed at ambient pressure and under an electric field. Under the optimum conditions, limits of detection and quantification were achieved in the ranges of 1.52-2.73 and 5.1-9.1 ng g -1 , respectively. The relative standard deviations were less than 8% for intra- (n = 6) and inter-day (n = 4) precisions at a concentration of 20 ng g -1 of each analyte. Finally, the proposed method was applied to the analysis of the studied antibiotics in fifteen different sausage samples marketed in Tabriz, Iran. Oxytetracycline was determined in three of the studied sausage samples.

What is known and Objective: Long-acting intramuscular penicillin G injection is an important product for the management of some severe infections. However, testing the bioequivalence of such long-acting formulations is difficult. Our aim was to undertake such a test using a generic formulation containing 1 200 000 IU of benzathine penicillin G powder and an innovator's product (Retarpen® 1·2 million units; Sandoz, Switzerland). Methods: In an open, double-blind, randomized, two-periods, two-group crossover study, 12 healthy male volunteers received both formulations of benzathine penicillin G on two different days with a 5-month washout period between the doses and a sampling period of over 500 h. A simple, sensitive and rapid high-performance liquid chromatography (HPLC)-UV method was developed and validated for determination of penicillin G plasma concentrations and other pharmacokinetic (PK) parameters. Results and Discussion: The analytical method used produced linear responses within a wide analyte concentration range with average within-run and between-run variations of below 15% with acceptable recovery, accuracy and sensitivity. The primary PK parameters we used were maximum plasma concentration ( Cmax), time to reach the maximal concentration ( Tmax) and the area under the plasma concentration vs. time curve from time zero to the last sampling time (AUC0→t) using a standard non-compartmental approach. Based on these parameters, the two formulations were bioequivalent. What is new and Conclusion: We illustrate the bioequivalence testing of a very long-acting product. The data indicate that the generic test formulation and the branded reference formulation were bioequivalent in fasting healthy Iranian male volunteers. [ABSTRACT FROM AUTHOR]