Furthermore, this near-POC assay could be easily taylored to detect either new DRMs or DRM of from various HIV clades and might be useful for pre-therapy screening in LMICs with high levels of transmitted drug resistance.Investigation on the distribution of persistent organic pollutants (POPs) in aquatic organisms is of great importance for exploring the biological toxicity and health risks of environmental pollutants. In this study, a liquid extraction surface analysis mass spectrometry (LESA-MS) method was developed for rapid and in situ analysis of the spatial distribution of perfluoroalkyl substances (PFASs) in zebrafish. By combining the high-precision automated moving platform of LESA device and the high-resolution MS, quantitative analysis of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in zebrafish tissue section were easily achieved. A tissue-specific ionization efficiency factor (TSF) strategy was also proposed to correct the matrix effect in different parts of zebrafish tissue. By using the developed method, high sensitive and efficient imaging of PFOA and PFOS in zebrafish tissue was achieved, and the distributions of PFOA and PFOS in descending order were gills, organs, roes, pelvic fin, muscle, and brain. The experimental results demonstrated that the coupling of LESA-MS method with TFS strategy is an efficient and reliable approach for monitoring the content distribution of environmental pollutants in biological tissues.Based on green analytical chemistry principles it is important to evolve procedures that convert solid samples into solutions without using excessive reagent quantities, energy, temperature, and avoiding waste generation. To reach this aim, a simple infrared assisted digestion (IRAD) method for animal feed analysis was proposed. Infrared radiation (IR) with 2 mL of HNO3 and 2 mL of H2O2 were assessed, presenting low dissolved organic carbon (DOC) and residual acidity (RA) in the final digest, being fully compatible with microwave induced plasma atomic emission spectrometry (MIP OES). Calcium, Cd, Cu, Fe, K, Mg, Na, P, Sr and Zn were determined in reference materials and in animal feeds. Limits of quantification were between 2.52 and 284 mg kg-1 for Ca and P respectively. Recovery values ranged 80-120%, with relative standard deviations (RSD%) under 8%. The friendliness offered by the IRAD MIP OES method was evaluated by two green indexes. Concentrations in feedstuffs were compared with National Research Council (NRC) recommendations.Magnetic-based microextraction approaches have gained popularity in recent years due to the magnetic properties of the extraction phases allowing to handle them easier and more efficiently. This work describes a magnetic-based analytical method for the determination of the family of nitro musks in environmental water samples. These compounds have been of great concern due to their environmental impacts and potential health effects. The method is based on stir bar sorptive-dispersive microextraction (SBSDME) as extraction approach, prior to thermal desorption coupled to gas chromatography-mass spectrometry analysis (TD-GC-MS). For this purpose, polydopamine-coated cobalt ferrite magnetic nanoparticles (CoFe2O4@PDA) were used as extraction material. The main parameters involved in the extraction procedure (i.e., sorbent amount, extraction time and ionic strength) as well as in the thermal desorption step (i.e., temperature and desorption time) were evaluated in order to obtain the highest sensitivity. Under the selected conditions, the method showed good linearity, limits of detection and quantification in the low ng L-1 range, intra- and inter-day repeatability with RSD less then 15%, and high enrichment factors (178-640). Finally, the method was applied to four environmental water samples of different origin. Relative recovery values ranging from 91 to 120% highlighted that the matrices under consideration do not affect the extraction process. This work constitutes the first time in which nitro musks compounds were selectively extracted by taking advantage the high potential that magnetic-based microextraction techniques offer, specially SBSDME.With a dramatic increase in the incidence of obesity, it is significant to screen lipase inhibitors from traditional herbal medicines as drugs to treat obesity. Lipase inhibitors currently used to treat obesity possess the defects of toxicity and off-target effects. Thus, there is an urgent need to explore more safe, effective and targeted anti-obesity drugs from traditional herbal medicines. In this work, amino functionalized magnetic cellulose microsphere was employed as a novel support to immobilize lipase through covalent bonding. Characterizations from fourier transform infrared spectroscopy, transmission electron microscopy and X-ray diffraction demonstrated the successful preparation of the support. In comparison with the free lipase, the immobilized lipase manifested the excellent properties of a wider range for pH and temperature endurance, better pH, thermal, storage stability and reusability. Through investigating the kinetics performances of the immobilized lipase, the Michaelis-Menten constant was calculated to be 2.05 mM and its inhibition constant for orlistat was ascertained to be 40.74 μM. Eventually, the established strategy was applied to screen lipase inhibitors from 7 traditional herbal medicines and Crataegus pinnatifida Bunge was screened out due to its significant lipase inhibitory activity. To sum up, our newly established method not only developed a platform for efficiently discovering novel anti-obesity drugs from traditional herbal medicines, but also laid a solid foundation for successfully exploring undiscovered medicinal value of the traditional herbal medicines.One-pot magnetic separation of uranium (U) in seawater and groundwater samples has been made possible by synthesizing phosphoramidate functionalized Ag coated citrate-Fe3O4 nanoparticles (NPs). The magnetic saturation value of these functionalized NPs is 27.1 emu g-1. The synergistic extraction mechanism of U(VI) ion by the surface-modified phosphoramidate and citrate molecules make these NPs highly selective towards U(VI). The adsorption kinetics follows a pseudo-second-order model and the adsorption isotherm fits successfully to the Langmuir adsorption model. The functionalized NPs show quantitative extraction efficiency in the pH range of 6.5-8 with a maximum loading capacity (Qm) of 108.7 mg g-1. https://www.selleckchem.com/products/k03861.html The equilibration time required by these functionalized NPs to attain the Qm value is 120 s. The recycling of these NPs can be done up to 5-6 times with 1.0 mol L-1 of Na2CO3 or NH4OH for quantitative extraction of U(VI). These functionalized NPs show high resilience towards large number of naturally abundant metal ions.
Furthermore, this near-POC assay could be easily taylored to detect either new DRMs or DRM of from various HIV clades and might be useful for pre-therapy screening in LMICs with high levels of transmitted drug resistance.Investigation on the distribution of persistent organic pollutants (POPs) in aquatic organisms is of great importance for exploring the biological toxicity and health risks of environmental pollutants. In this study, a liquid extraction surface analysis mass spectrometry (LESA-MS) method was developed for rapid and in situ analysis of the spatial distribution of perfluoroalkyl substances (PFASs) in zebrafish. By combining the high-precision automated moving platform of LESA device and the high-resolution MS, quantitative analysis of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in zebrafish tissue section were easily achieved. A tissue-specific ionization efficiency factor (TSF) strategy was also proposed to correct the matrix effect in different parts of zebrafish tissue. By using the developed method, high sensitive and efficient imaging of PFOA and PFOS in zebrafish tissue was achieved, and the distributions of PFOA and PFOS in descending order were gills, organs, roes, pelvic fin, muscle, and brain. The experimental results demonstrated that the coupling of LESA-MS method with TFS strategy is an efficient and reliable approach for monitoring the content distribution of environmental pollutants in biological tissues.Based on green analytical chemistry principles it is important to evolve procedures that convert solid samples into solutions without using excessive reagent quantities, energy, temperature, and avoiding waste generation. To reach this aim, a simple infrared assisted digestion (IRAD) method for animal feed analysis was proposed. Infrared radiation (IR) with 2 mL of HNO3 and 2 mL of H2O2 were assessed, presenting low dissolved organic carbon (DOC) and residual acidity (RA) in the final digest, being fully compatible with microwave induced plasma atomic emission spectrometry (MIP OES). Calcium, Cd, Cu, Fe, K, Mg, Na, P, Sr and Zn were determined in reference materials and in animal feeds. Limits of quantification were between 2.52 and 284 mg kg-1 for Ca and P respectively. Recovery values ranged 80-120%, with relative standard deviations (RSD%) under 8%. The friendliness offered by the IRAD MIP OES method was evaluated by two green indexes. Concentrations in feedstuffs were compared with National Research Council (NRC) recommendations.Magnetic-based microextraction approaches have gained popularity in recent years due to the magnetic properties of the extraction phases allowing to handle them easier and more efficiently. This work describes a magnetic-based analytical method for the determination of the family of nitro musks in environmental water samples. These compounds have been of great concern due to their environmental impacts and potential health effects. The method is based on stir bar sorptive-dispersive microextraction (SBSDME) as extraction approach, prior to thermal desorption coupled to gas chromatography-mass spectrometry analysis (TD-GC-MS). For this purpose, polydopamine-coated cobalt ferrite magnetic nanoparticles (CoFe2O4@PDA) were used as extraction material. The main parameters involved in the extraction procedure (i.e., sorbent amount, extraction time and ionic strength) as well as in the thermal desorption step (i.e., temperature and desorption time) were evaluated in order to obtain the highest sensitivity. Under the selected conditions, the method showed good linearity, limits of detection and quantification in the low ng L-1 range, intra- and inter-day repeatability with RSD less then 15%, and high enrichment factors (178-640). Finally, the method was applied to four environmental water samples of different origin. Relative recovery values ranging from 91 to 120% highlighted that the matrices under consideration do not affect the extraction process. This work constitutes the first time in which nitro musks compounds were selectively extracted by taking advantage the high potential that magnetic-based microextraction techniques offer, specially SBSDME.With a dramatic increase in the incidence of obesity, it is significant to screen lipase inhibitors from traditional herbal medicines as drugs to treat obesity. Lipase inhibitors currently used to treat obesity possess the defects of toxicity and off-target effects. Thus, there is an urgent need to explore more safe, effective and targeted anti-obesity drugs from traditional herbal medicines. In this work, amino functionalized magnetic cellulose microsphere was employed as a novel support to immobilize lipase through covalent bonding. Characterizations from fourier transform infrared spectroscopy, transmission electron microscopy and X-ray diffraction demonstrated the successful preparation of the support. In comparison with the free lipase, the immobilized lipase manifested the excellent properties of a wider range for pH and temperature endurance, better pH, thermal, storage stability and reusability. Through investigating the kinetics performances of the immobilized lipase, the Michaelis-Menten constant was calculated to be 2.05 mM and its inhibition constant for orlistat was ascertained to be 40.74 μM. Eventually, the established strategy was applied to screen lipase inhibitors from 7 traditional herbal medicines and Crataegus pinnatifida Bunge was screened out due to its significant lipase inhibitory activity. To sum up, our newly established method not only developed a platform for efficiently discovering novel anti-obesity drugs from traditional herbal medicines, but also laid a solid foundation for successfully exploring undiscovered medicinal value of the traditional herbal medicines.One-pot magnetic separation of uranium (U) in seawater and groundwater samples has been made possible by synthesizing phosphoramidate functionalized Ag coated citrate-Fe3O4 nanoparticles (NPs). The magnetic saturation value of these functionalized NPs is 27.1 emu g-1. The synergistic extraction mechanism of U(VI) ion by the surface-modified phosphoramidate and citrate molecules make these NPs highly selective towards U(VI). The adsorption kinetics follows a pseudo-second-order model and the adsorption isotherm fits successfully to the Langmuir adsorption model. The functionalized NPs show quantitative extraction efficiency in the pH range of 6.5-8 with a maximum loading capacity (Qm) of 108.7 mg g-1. https://www.selleckchem.com/products/k03861.html The equilibration time required by these functionalized NPs to attain the Qm value is 120 s. The recycling of these NPs can be done up to 5-6 times with 1.0 mol L-1 of Na2CO3 or NH4OH for quantitative extraction of U(VI). These functionalized NPs show high resilience towards large number of naturally abundant metal ions.
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