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Compared with the traditional fluorescence turn-off approach, our newly designed probe significantly improved the sensitivity (10 times) and demonstrated excellent specificity. This rapid, label-free, and low-cost fluorescence enhancing method can potentially be applied in the diagnosis of miR-223 associated disease, such as IBD.The separation of chiral amino acids using microchip electrophoresis (MCE) was investigated using chiral nematic mesoporous silica (CNMS) as the chiral stationary phase, with hydroxypropyl-β-cyclodextrin (HP-β-CD) as the chiral selector. Individually, neither CNMS nor HP-β-CD achieved separation, so they were combined. Ten chiral amino acids (phenylalanine, tryptophan, glutamic, alanine, serine, aspartic acid, cysteine, methionine, tyrosine, and histidine) were selected as the model analytes. Under optimized conditions, we achieved baseline separation of six chiral amino acids, and the other four chiral amino acids displayed improved resolution. These results indicate the presence of a synergistic effect between CNMS and HP-β-CD, showing that the combination of a chiral stationary phase and a chiral additive is a promising approach for enantioseparation using MCE.A device utilizing atmospheric pressure glow discharge as the second excitation source coupled with laser ablation (LA) for direct solid sampling was developed, with few operating costs and low gas consumption. This new device was first utilized for the highly sensitive determination of Zn, Pb, and Cd elements in complex matrix soil samples. It also provided a new method for monitoring these three trace elements in soil samples. Good linearity was observed in the quantitative results for Zn, Pb, and Cd detection, and the respective linear correlation coefficients (R2) were 0.9953, 0.9897, and 0.9961. Moreover, the limit of detection (LOD) of 0.68, 2.71, and 0.31 mg kg-1 were achieved for Zn, Pb, and Cd, respectively; the LOD of Zn reduced by more than one order of magnitude compared to that observed in laser-induced breakdown spectroscopy results. In addition, the quantitative analysis results showed good agreement with the certified values and those obtained of ICP optical emission spectrometry, proving the detection accuracy and practicability of the developed device.A simple cost-effective moving drop device, with solenoid valves control for programmable liquid handling, was developed for electrokinetic injection in capillary zone electrophoresis (CZE). With a CZE of 50-μm bore fused silica capillary tube and contactless conductivity detector (C4D), mixed anions (Cl-, NO3-, and SO42- as the model) solution was injected at the ground side. Simultaneous quantitative chemical analysis can be achieved. A linear relationship of concentration and the peak height was achieved in the range of 0.5-10 mg L-1 for each anion, with LOD and LOQ being 0.02 mg L-1 and 0.5 mg L-1, respectively. The MVD-CZE system allows continuous operation with a sample throughput of 40 samples/hour. A real sample application was demonstrated for air samples, with one drop (25 μL) collected from a midget bubbler based air sampling unit. The recoveries were found to be 74.4-115.0 %. AZD2171 cost The developed device was also preliminarily applied for the injection of mixed cations (NH4+, Na+, K+, Ca2+, and Mg2+) at the high voltage side end with optimistic results.Heavy metal ions in water resources present great threats to human health. Chromium (Cr), as the frequently used heavy metal in industrial processes and everyday life, requires a low-cost, fast and effective means to determine its concentration, especially in drinking water. Conventional colorimetric paper-based analytical devices (PADs), due to the limited sensitivity, are unable to quantify the most harmful heavy metal ions to the drinking water standard. In this work, we present a method of using a superhydrophobic (SH) paper to concentrate Cr6+ from solutions of very low concentration to obtain the precipitated Cr6+ salt particulates. A known volume of Cr6+-containing solution was concentrated to "a spot" on the SH paper through drying, so that trace amount of Cr6+ can be quantified via the application of a specifically-designed chemical-responsive adhesive tape (CAT) sensor, loaded with Cr6+- specific indicator, on to the concentrated Cr6+ spot. The detection limit of the SH-CAT method for Cr6+ is 0.05 mg/L, which is the permitted maximum concentration in drinking water and is significantly lower than that of conventional PADs. The interference and the accuracy studies also show the reliability of this method for measuring trace amounts of analytes.The paper reports on the development of an analytical method based on the use of a new miniaturised short-wave infrared (SWIR) spectrometer for the analysis of cultural heritage samples. The spectrometer is a prototype characterised by small dimension (45.0 mm in diameter x 47.5 mm in height x 60 g weight), easily handled and transferable out of research laboratories. The prototype enables the acquisition of spectra in the SWIR range of 1200-2200 nm, which is a unique feature for miniaturised spectrometers. The exploitation of this spectral range allows the detection of a high number of combination and overtone bands, which guarantees significant diagnostic power to the instrument. The present study lays a significant foundation to the development of analytical strategies based on miniaturised NIR spectrometers working in the SWIR spectral range for the characterization of complex samples such as cultural heritage specimens. Analytical performances of the new spectrometer were assessed on archaeological bones, cinematographic films and bronze patinas. The selected cases of study present challenging conservation issues not properly addressed, and their analyses usually require to be performed on-site, in places not easily accessible by restorers, archaeologists and/or scientists. The data acquired with the prototype, combined with a multivariate data analysis approach, show the possibility to i) differentiate between the materials used as a support for cinematographic film namely cellulose nitrate (CN), cellulose acetates (CA) and polyethylene terephthalate (PET); ii) sort out archaeological bone fragments according to their collagen content as an initial screening test for bones characterization; iii) differentiate between corrosion products on outdoor bronze sculpture, which is important for assessing the state of conservation of the artwork. The prototype enabled rapid information acquisition to guide restoration strategies, which need to be supported in real time by quick and easy analytical procedures.

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