Separation and quantification of diazinon in water samples using liquid-phase microextraction-based effervescent tablet-assisted switchable solvent method coupled to gas chromatography-flame ionization detection.

This study used a liquid-phase microextraction-based effervescent tablet-assisted switchable solvent method coupled to gas chromatography-flame ionization detection as an eco-efficient, convenient-to-use, cost-effective, sensitive, rapid, and efficient method for extracting, preconcentrating, and quantifying trace amounts of diazinon in river water samples. As a switchable solvent, triethylamine (TEA) was used. In situ generation of CO2 using effervescent tablet containing Na2 CO3 and citric acid changed the hydrophobic TEA to the hydrophilic protonated triethylamine carbonate (P-TEA-C). CO2 removal from the specimen solution using NaOH caused P-TEA-C to be converted into TEA and led to phase separation, during which diazinon was extracted into the TEA phase. The salting-out process was helpful in enhancing extraction efficiency. In addition, a number of significant parameters that affect extraction recovery were examined. Under optimum conditions, the limit of detection and limit of quantitation were 0.06 and 0.2 ng/ml, respectively. The extraction recovery percentage and pre-concentration factor were obtained at 95 and 190%, respectively, and the precision (inter- and intra-day, relative standard deviation %, n = 5) was <5%.

The electrocardiographic, hemodynamic, echocardiographic, and biochemical evaluation of treatment with edaravone on acute cardiac toxicity of aluminum phosphide.

Aluminum phosphide (AlP) poisoning can be highly fatal due to its severe toxicity to the heart. Based on the evidence, edaravone (EDA) has protective effects on various pathological conditions of the heart. This research aimed to examine the potential protective effects of EDA on AlP-induced cardiotoxicity in rats. The rats were divided into six groups, including almond oil (control), normal saline, AlP (LD50), and AlP + EDA (20, 30, and 45 mg/kg). Thirty minutes following AlP poisoning, the electrocardiographic (ECG), blood pressure (BP), and heart rate (HR) parameters were examined for 180 min. The EDA was injected 60 min following the AlP poisoning intraperitoneally. Also, 24 h after poisoning, echocardiography was carried out to evaluate the ejection fraction (EF), stroke volume (SV), and cardiac output (CO). The biochemical and molecular parameters, such as the activities of the mitochondrial complexes, reactive oxygen species (ROS), apoptosis and necrosis, and troponin I and lactate levels, were also examined after 12 and 24 h in the heart tissue. According to the results, AlP-induced ECG abnormalities, decrease in blood pressure, heart rate, SV, EF%, and CO were significantly improved with EDA at doses of 30 and 45 mg/kg. Likewise, EDA significantly improved complex I and IV activity, apoptosis and necrosis, ROS, troponin I, and lactate levels following AlP-poisoning (p < 0.05). Also, the mean survival time was increased following EDA treatment, which can be attributed to the EDA's protective effects against diverse underlying mechanisms of phosphine-induced cardiac toxicity. These findings suggest that EDA, by ameliorating heart function and modulating mitochondrial activity, might relieve AlP-induced cardiotoxicity. Nonetheless, additional investigations are required to examine any potential clinical advantages of EDA in this toxicity.

Development of effervescence-assisted switchable polarity solvent homogeneous liquid-phase microextraction for the determination of permethrin and deltamethrin in water samples prior to gas chromatography-flame ionization detection.

An effervescent tablet-assisted switchable polarity solvent-based homogeneous liquid-phase microextraction combined with gas chromatography with flame ionization detection has been conducted for the separation, preconcentration, and detection of permethrin and deltamethrin in the river water specimens. Triethylamine (TEA) was utilized as the switchable polarity solvent in this method. The switching process was carried out by the dissolution of an effervescent tablet including an effervescency agent (sodium carbonate) and a proton donor agent (citric acid). Changing the pH of the specimen solution enhanced the conversion of TEA into protonated triethylamine carbonate through the tablet that generated carbon dioxide bubbles in situ. Finally, the addition of sodium hydroxide changed the ionization state of TEA and separated the two phases. Influential factors in the extraction were investigated. According to optimal situations, the limit of detection and the limit of quantification were 0.16 and 0.5 µg L-1 for permethrin and 0.03 and 0.1 µg L-1 for deltamethrin, respectively. The preconcentration factor was 194 in river water samples and inter- and intra-day precision (relative standard deviation %; n = 5) was <5%. The extraction recovery was obtained in the range of 93.0%-97% for permethrin and deltamethrin in water samples.

Ion-pair switchable-hydrophilicity solvent-based homogeneous liquid-liquid microextraction for the determination of paraquat in environmental and biological samples before high-performance liquid chromatography.

An approach involving ion-pair switchable-hydrophilicity solvent-based homogeneous liquid-liquid microextraction coupled to high-performance liquid chromatography has been applied for the preconcentration and separation of paraquat in a real sample. A mixture of triethylamine and water was used as the switchable-hydrophilicity solvent. The pH was regulated using carbon dioxide; hence the ratio of the ionized and non-ionized form of triethylamine could control the optimum conditions. Sodium dodecyl sulfate was utilized as an ion-pairing agent. The ion-associate complex formed between the cationic paraquat and sodium dodecyl sulfate was extracted into triethylamine. The separation of the two phases was carried out by the addition of sodium hydroxide, which changed the ionization state of triethylamine. The effects of some important parameters on the extraction recovery were investigated. Under the optimum conditions (500 µL of the extraction solvent, 1 mg sodium dodecyl sulfate, 2.0 mL of 10 mol/L sodium hydroxide, and pH 4), the limit of detection and the limit of quantification were 0.2 and 0.5 µg/L, respectively, with preconcentration factor of 74. The precision (RSD, n = 10) was  <5%. The recovery of the analyte in environmental and biological samples was in the range of 90.0-92.3%.