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Martens Gustafsson posted an update 4 days, 12 hours ago
The experimental results are of great significance for arsenopyrite geological environment assess and removal of arsenic ions. Few time-consuming bioanalytical methods are currently available for trabectedin quantification in clinical investigations. Here we present a novel, fast and sensitive method for trabectedin determination in human plasma based on hydrophilic interaction liquid chromatography and tandem mass spectrometry (HILIC-MS/MS). Plasma samples are treated with acetonitrile-0.1 % formic acid and the solvent extract is directly injected into an Acquity BEH Amide column (2.1 × 100 mm, 1.7 μm) operating in HILIC mode at 0.2 mL/min with 8020 acetonitrile-0.1 % formic acid in water. The analyte is separated by an organic solvent gradient and quantified by an Agilent Ultivo triple quadrupole mass spectrometer operating in multiple reaction monitoring (MRM) mode. The quantitative MRM transitions were m/z 762→234 and m/z 765→234 for trabectedin and its d3-labeled derivative, respectively. The lower limit of quantification (LLOQ) was 0.01 ng/mL and the assay was linear up to 2.5 ng/mL. The intra- and inter-day relative error ranged from 1.19 % to 8.52 %, while the relative standard deviation was less than 12.35 %. The method was used to determine the pharmacokinetic profiles of trabectedin in 26 patients with soft tissue sarcoma, showing that this new HILIC-MS/MS method is suitable for use in clinical research. Host cell proteins (HCPs) in biotherapeutics can be identified by the use of enzymatic digestion and LC-MS/MS analysis. However, the major challenge is that HCPs are often present at very low levels in relation to the protein drug (low ppm-levels). In this study, the ProteoMiner™ Enrichment Kit (Bio-Rad) was evaluated as a strategy to enable identification of HCPs by LC-MS/MS by enrichment of low-abundant HCPs and a simultaneous depletion of the high-abundant product protein. A recombinant protein produced in Chinese hamster ovary (CHO) cells was spiked with six standard proteins at varying concentrations (10-1000 ppm). The sample was split into two aliquots; one that was prepared with the ProteoMiner™ Enrichment Kit and one control, where the enrichment procedure was omitted. The ProteoMiner™ Enrichment Kit was combined with the ProteoMiner Sequential Elution Large-Capacity Kit (Bio-Rad), eluting the proteins into four fractions. The samples were then digested with trypsin and analyzed with LC-MS/MS. In addibling their identification by LC-MS/MS. Here, we demonstrate use of acetylcholinesterase (AChE)-responsive polyoxometalate (POM)/surfactant supramolecular spheres to build a liquid crystal (LC)-based sensing platform for detection of organophosphorus pesticides. The self-assembled spheres are composed of hybrid materials of a POM, sodium dodecatungstophosphate (PW12), and a surfactant, myristoylcholine (Myr). It displays dark appearance when the aqueous solution is in contact with LCs supported on the octadecyltrichlorosilane-treated glass deposited with the supramolecular spheres, suggesting perpendicular orientation of LCs at the aqueous/LC interface. In contrast, LCs show bright appearance when the surface-deposited supramolecular spheres are enzymatically hydrolyzed by AChE, corresponding to planar orientation of LCs at the aqueous/LC interface. Detection of organophosphates are successfully achieved as they are potent inhibitors of AChE. The detection limit of the sensing platform reached 0.9 ng/mL for dimethoate. This method can avoid disturbance of external interference with excellent specificity and sensitivity, which makes it very promise in detection of organophosphorus pesticides. A novel dendritic silicon dioxide nanocomposite coated with a highly dispersed graphene-like boron nitride nanosheet (g-BN(x)@SiO2) was in-situ synthesized and employed as a solid-phase extraction material for the Rhodamine B (RhB) and Rhodamine 6G (R6G) enrichment in food samples prior to their quantitation by HPLC. The structures and morphologies of g-BN(x)@SiO2 were characterized by XRD, FTIR, BET and TEM. The adsorption performance and mechanism were investigated and showed an enhanced maximum adsorption capacity of 625 mg/g for RhB on the nanocomposite loaded with 1% of g-BN via a fast, spontaneous process. Under optimal extraction conditions, this method showed low detection and quantification limits (2.8 μg/L for RhB, 2.1 μg/L for R6G and 9.2 μg/L for RhB, 6.9 μg/L for R6G, respectively), good repeatability (RSD% less then 3.7%), and satisfactory spiked recoveries of 94.8%-103.1% for RhB and R6G in real chili powder and beverage. Therefore, the g-BN(1%)@SiO2-based materials possess significant potential. Enzymatic desulfation using arylsulfatase provides an attractive approach to improve agar quality. We have previously characterized a functional arylsulfatase from Pseudoalteromonas carrageenovora. To further improve its enzymatic performance, we isolated a mutant arylsulfatase of K253Q with improved enzyme activity from a random mutant library. Decursin in vitro Compared to wild-type arylsulfatase (WT), K253Q showed 33% increase in enzyme activity, with optimal temperature and pH of 55 °C and 8.0, respectively. K253Q demonstrated better substrate binding ability with lower Km value. Structure analysis indicated that a combination of the additional hydrogen bond and the enhanced substrate binding affinity could account for the improved enzyme activity of K253Q. K253Q exhibited about 54% sulfate removal against agar, resulting in additional 8% increase in 3,6-AG content and 20% increase in gel strength compared to WT. Scanning electron microscopy showed that K253Q treatment led to a stronger crosslinking structure of agar. Wild edible plants are recently recognized as an important source of acquiring macro and micro nutrients beneficial for human health. Hence, the present study was undertaken to assess the antidiabetic and antioxidant potentials, polyphenolic profile, – as well as the ascorbic acid, proximate and mineral compositions of five selected Bangladeshi wild plants. The studied samples were rich in ash, fiber, protein, vitamin C and low in fat. The undertaken plant samples were found to have good amounts of total phenolic, total flavonoid, and antioxidant capacities, documented by DPPH, FRAP, and TEAC assays. They also exhibited varying spectrum of polyphenols estimated by HPLC. Significant inhibition of α-amylase activity by plant extracts was also observed. Evaluation by principal component analysis revealed clear separation among the wild plant varieties. The study findings would enrich the food composition table of Bangladesh and allow the population to consume more wild plants and increase their production.