Connectomebased forecast of global intellectual performance within people who have HIV

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A novel sensitive method for the determination of the five primary metabolites of phthalate esters (PAEs) in urine was developed by combining dispersive liquid-liquid microextraction (DLLME) using ionic liquids with high performance liquid chromatography (HPLC). The factors affecting the efficiency of DLLME were optimized. The types and proportions of extraction solvent and dispersants, as well the ultrasonic extraction time, cooling time, and centrifugal time, were determined. The optimal conditions were as followsextraction solvent[C8MIM]PF6] 35 μL; dispersants[BSO3HMIm]OTf] 30 μL,[C4MIM]BF6] 120 μL; NH4PF6 0.1 g, extraction at 35℃, ultrasonic dispersion for 5 min, cooling in ice water for 5 min, centrifugation at 4000 r/min for 5 min. After optimization, the five primary metabolites of PAEs were determined. The method showed a good linear relationship within the concentration range of 0.5-1000 μg/L. The determination coefficients (R2) were greater than 0.9955. The detection limit was in the range of 0.16-0.19 μg/L. Under the optimized conditions, the extraction recoveries for the PAEs were 92.9%-105.0%, and the relative standard deviations (RSDs) of the intra- and inter-day precisions were less then 5.96%. Urine samples collected from 10 diabetic patients were tested, and the exposure level of the population to the PAE metabolites was evaluated. All the PAE metabolites were detected in these samples, and the detection rate of 2-ethylhexyl hydrogen phthalate (MEHP) was 100%. In conclusion, no toxic organic reagents were added during the extraction process in this method, and multifunctional ionic liquids were used as the extraction agent, dispersant, and salting-out agent. In other words, the extraction process was demonstrated to be green, simple, and efficient. The developed method has high sensitivity and stability, and it is suitable for the determination of trace PAE metabolites in human urine.Using o-phthalaldehyde (OPA) as the derivatization reagent, a precolumn derivatized -high performance liquid chromatography (HPLC) method was developed for the simultaneous determination of amino acid neurotransmitters taurine (Tau), glutamic acid (Glu), glycine(Gly), and γ -aminobutyric acid (γ-GABA), as well as the monoamine neurotransmitter dopamine (DA), in serum samples. The samples and ethanol were mixed at a volume ratio of 12 (v/v) for protein precipitation. After centrifugation, the supernatant was withdrawn and blown to dryness using nitrogen. The residue was pre-column derivatized with OPA, and the derivatized product was isolated by gradient elution ona Luna 5u C18 column (250 mm×4.6 mm, 5 μm). Under the optimal experimental conditions, the five neurotransmitters showed good linearities (r2 ≥ 0.9866). The limits of detection were between 0.10 and 0.40 μmol/L. The spiked recoveries at different spiked levels were 87.57%-115.31%, and the RSDs were below 7.80%. This method is simple, sensitive, and it can be promised for the simultaneous detection of amino acid and monoamine neurotransmitters.Archaea are single-cell microorganisms, structurally and biochemically similar to bacteria and fungi. Most of them live in extreme environments, such as high salt, extremely acidic, extremely hot, and anaerobicenvironments. The membrane structure and related metabolic pathways of archaea are different from those of other microorganisms. Therefore, studying the lipid metabolism of archaea is of great significance for exploring the life activities in extreme environments. As the first step in lipidomic analysis, lipid extraction and pretreatment methods play an important role, as they influence the accuracy and reliability of the final results. We harnessed ultra-performance liquid chromatography coupled with high-resolution mass spectrometry (UPLC-HRMS) to detect the total normal lipids. The hyperthermophilic archaeon Pyrococcus yayanosii was selected as the model. The Bligh-Dyer acidic method, Folch method, methyl tert-butyl ether (MTBE) method, and solid-phase extraction (SPE) method were compared by multi-component analysis in terms of extraction efficiency, reproducibility, and extraction discrimination. Comprehensive analysis revealed that the SPE and MTBE methods showed the best extraction repeatability and extraction efficiency, and were suitable for high-throughput microbial lipid extraction. Finally, normal lipid components of P. yayanosii were comprehensively analyzed by SPE coupled with UPLC-HRMS. Ruboxistaurin ic50 A total of 1402 lipid components were identified. This article aims to provide a reference for non-targeted lipidomic analysis of archaea and other microorganisms towards understanding their lipid metabolism.A method based on liquid chromatography coupled with high-resolution quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) was developed for the simultaneous screening and determination of fentanyl and its 26 analogs in liquid and solid powder drugs. The established method involves successive extraction by 5 mL 75% (v/v) acetonitrile aqueous solution and 5 mL acetonitrile, followed by clean-up using the hydrophilic lipophilic balance (HLB) solid-phase extraction method. Detection was achieved by electrospray ionization (ESI) in the positive mode, TOF-MS, and information-dependent acquisition (IDA)-MS/MS acquisition; the external standard method was adopted for quantification. Two databases of accurate mass and fragment ions were created. The standard matrix-matched calibration curves of the 27 target compounds were linear in the range of 5.00-100 μg/L, with the correlation coefficients (r2)>0. 99. The limits of quantification for the 27 target compounds were 10.0 μg/kg. The recoveries for all the target compounds in vitamin C tablet, headache powder, cough syrup, and transdermal patch samples were in the ranges of 82.9%-106%, 84.8%-106%, 86.9%-109%, and 83.1%-106%, respectively, with relative standard deviations ranging from 0.38% to 8.71% (n=6). The results demonstrated that the developed method is rapid and sensitive for the simultaneous monitoring and determination of fentanyl and 26 its analogs in liquid and solid powder drugs.