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It can simply, efficiently and directly screen and identify potential α-glucosidase inhibitors from natural sources. This method was expected to provide an effective basis for accelerating the development of new hypoglycemic drugs.Tryptamines are hallucinogenic substances many of which have appeared recently as novel psychoactive substances (NPS). Herein, we describe the establishment of a rapid UHPLC-MS/MS quantitative method for the targeted screening of 16 tryptamines of abuse in hair. Twenty milligram pieces of hair were pulverized below 4 °C in 0.5 mL of deionized water containing 0.1% formic acid and an internal standard (2 ng/mL psilocin-d10 and psilocybin-d4). After subsequent centrifugation, 5 μL of the supernatant was injected into a LC-MS/MS system fitted with a Waters Acquity UPLC HSS T3 column (100 mm × 2.1 mm, 1.8 μm). The column was gradient eluted at 0.3 mL/min with mobile phases composed of 20 mmol/L ammonium acetate, 5% acetonitrile, and 0.1% formic acid in water (solvent A) and acetonitrile (solvent B). Limits of detection ranged between 0.1 and 20 pg/mg, with limits of quantitation ranging from 3 to 50 pg/mg. The calibration curves for all analytes were linear (r &gt; 0.992). Accuracies varied between 91% and 114%, with intraday precision RSDs less then 14% and interday precision RSDs of between 1.3% and 14%. The recoveries of all tryptamines were in the 85-115% range, with the matrix effect ranging from 95% to 112%. [https://www.selleckchem.com/products/en450.html read more] The validated method was successfully used to analyse 191 hair samples from suspected tryptamine users, 77 of which were 5-MeO-DiPT-positive, while the 16 tryptamines and their metabolites were not detected in the remaining 114 hair samples. 5-MeO-DiPT and its 5-MeO-NiPT, 5-OH-DiPT, and 4-OH-DiPT metabolites were concurrently detected in 34 hair samples. 5-MeO-DiPT, as the parent drug, was the parent substance found in the hair samples.Pesticides are chemicals widely applied in agriculture and proven environmental contaminants; their hazards include harmful effects on human health, therefore the evaluation of exposure is relevant to risk assessment. Hair is a non-invasive specimen that incorporates pollutants allowing an extended exposure window to be surveyed. Aim of this work was to develop and validate an assay for measuring 41 pesticide active principles in human hair. Under optimised conditions, analytes were extracted by soaking hair in acetonitrile, in the presence of internal standards, under stirring and heating condition. Chemical separation was achieved using liquid chromatography with silica-based bonded phase chromatographic column. Detection and quantification were performed, with both positive and negative electrospray ionization, by a hybrid triple quadrupole/linear ion trap mass spectrometer operating in the scheduled selected reaction monitoring mode. The validated assay showed a linear dynamic range up to 10000 ng/L or 400 pg/mg hair, inter- and intra-run precisions less then 7%, and accuracies within 10% of theoretical concentrations. Limits of quantification were 1 ng/L or 0.04 pg/mg hair for most of the investigated pesticides. Matrix effect experiments showed that the use of internal standards allowed for the control of biases. The method was applied to the determination of pesticides in hair samples form occupationally and non-occupationally exposed individuals. The results of this study indicate that the developed assay is useful to assess pesticides in human hair following different exposure scenarios.Extraction of polar acidic compounds is a challenging task in electromembrane extraction. In this study, gel-electromembrane extraction was employed for the extraction of phenolic acids as the polar acidic compounds from fruit juices. For this aim, the extraction of phenolic acids from the juice samples (4 mL, pH = 6.0) was carried out across the agarose gel membrane (concentration of agarose; 3% (w/v), pH of gel; 10.0, and thickness of membrane 3 mm) into the acceptor solution (100 μL, pH = 12.0). Also, this extraction process was conducted by applying the optimum potential (25 V) for 15 min to the extraction system. Under the optimized condition, acceptable linearity (R2 ≥ 0.993) over a concentration range of 10.0-2500 ng mL-1 was achieved. The limits of detection were between 3.0 and 15.2 ng mL-1, while the corresponding repeatabilities ranged from 5.3 to 11.4% (n = 4). The recoveries achieved for the extraction of target compounds were ranged from 26.8 to 74.4%. The proposed method was used for the extraction of phenolic acids from orange, apple and kiwi juices, and the obtained relative recoveries in the range of 78.0-104.2% and RSDs in the range of 6.3 to 11.3% indicated successful extraction of phenolic acids.A simple, rapid, cost-effective and sensitive high-performance liquid chromatography method with diode array detection was developed and validated for the quantification of letermovir, a compound approved for prophylaxis of cytomegalovirus infection and disease in adult recipients of an allogeneic hematopoietic stem cell transplant. Sorafenib was used as internal standard. Samples were pre-treated by liquid-liquid extraction with tert-butyl methylether. Separation was achieved on a XTerra® RP18 column (150 × 2.1 mm, 5 µm) at 30 °C using gradient elution with a mobile phase of 20 mM ammonium bicarbonate pH 7.9 (mobile phase A) and acetonitrile20 mM ammonium bicarbonate (91 v/v) (mobile phase B). Samples were eluted at a flow rate of 0.3 mL/min throughout the 20-min run. UV wavelength mode was used, letermovir and sorafenib were monitored at 260 nm. The calibration curve was linear in a concentration range of 25-5000 ng/mL with correlation coefficients ≥ 0.99. Intra-day and inter-day accuracy expressed as relative error were -11.4-20% and -7.96-10.62%, respectively. Precision expressed as coefficient of variation was 1.44-3.15% (intra-day) and 1.17-1.93% (inter-day). The method was successfully applied for analysis of 128 letermovir levels demonstrating its usefulness for letermovir monitoring in routine clinical practice.Calvo et al. (2020) criticize a new seagrass rehabilitation method proposed by Alagna et al. (2019) and inspired by the Posidonia oceanica spontaneous recovery observed at Capo Feto (Sicily), were recolonization was detected almost exclusively on rubbles deployed to fill a pipeline trench. Calvo et al. (2020) claim that natural recovery occurred consistently also on dead matte along the eastern side of the trench, weakening the assumption on which the method is based. Here we show that the P. oceanica patches reported by these authors as new establishments were already documented in 2003 (Vega Fernandez et al., 2005) and are attributable to the fragmentation of the pristine meadow caused by altered sedimentation rate after an extensive dredging operation. Moreover, we outline the area of applicability of the method tested in Alagna et al. (2019) and provide a point-by-point rebuttal to the complaints of imprecise and misleading contents of the paper.