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From the results, we found that nano-MOFs have obviously better dispersity, a lower precipitation speed, a smaller standard deviation, ten times higher fluorescence intensities and a much lower LOD than bulk-MOFs. Finally, we draw a conclusion that nano-MOFs are more in line with the requirements of analytical performance as fluorescence sensors, and the size of MOFs as fluorescence sensors should be as small as possible.Transfusion of donor red blood cells (RBCs) is a crucial methodology required for the treatment of acute trauma and anaemia or for surgical procedures. Due to the many limitations of donor blood, numerous strategies have been explored to develop haemoglobin (Hb)-based oxygen carriers to be used as oxygen delivery systems. Ilomastat price However, since free Hb suffers from a lack of stability and short circulation times in blood, an encapsulation platform is needed. Herein, we entrap Hb within a type of metal organic framework (MOF)-based nanoparticle (MOF-NP). By doing so, Hb is protected from misfolding and denaturation, which is a crucial aspect to preserve its excellent oxygen binding and releasing properties. Furthermore, the porous structure of MOF-NPs allows for the diffusion of small molecules (i.e., oxygen) in and out of the system. Our results show that the Hb-loaded MOF-NPs (MOFHb-NPs) are monodisperse and show a small hydrodynamic diameter of ∼220 nm. Importantly, the structure and functionality of the encapsulated Hb are well preserved. To achieve long circulation in the bloodstream, we functionalized MOFHb-NPs with naturally derived RBC membranes and compared the stealth properties of the membrane-coated MOFHb-NPs with our previously reported PEGylation strategy. Protein adsorption and cell uptake studies demonstrate that both coatings are able to significantly decrease the adsorption of proteins and also diminish their uptake by macrophages and endothelial cells. Furthermore, both types of coatings endow MOFHb-NPs with good biocompatibility and oxygen binding and releasing properties. Overall, this study presents a novel oxygen carrier system which might find applications as a blood surrogate.We developed an electrochemical aptasensor based on cocoon-like DNA nanostructures as signal tags for highly sensitive and selective detection of Escherichia coli O157H7. The stable cocoon-like DNA nanostructures synthesized by the rolling circle amplification reaction were loaded with hemin as electrochemical signal tags to amplify the signals. The single-stranded DNA capture probes were modified on the surface of a Au electrode via a Au-S bond. The E. coli O157H7 specific aptamer and capture probe formed double-stranded DNA structures on the Au electrode. The aptamer preferentially bound to E. coli O157H7, causing the dissociation of some aptamer-capture probes and releasing some capture probes. Subsequently, the free capture probes hybridized with the DNA nanostructures through the cDNA sequence. Under optimal conditions, the change in the electrochemical signal was proportional to the logarithm of E. coli O157H7 concentration, from 10 to 106 CFU mL-1, and the detection limit was estimated to be 10 CFU mL-1. The electrochemical aptasensor could be readily used to detect various pathogenic bacteria and to provide a new method of early diagnosis of pathogenic microorganisms.Mineral flotation processes are controlled by monitoring the grade of the present minerals. The economy of the flotation process can be significantly improved by on-line analysis of minerals in a slurry. However, online and quantitative mineral identification of slurries is challenging. Industrial developers are demanding novel ideas enabling differentiation between minerals with similar elemental contents, such as scheelite and fluorite or gangue minerals, since they have different flotation properties. The primary focus of this research is the measurement of mineral contents from the elemental concentrations acquired by an on-stream slurry analyser based on X-ray fluorescence (XRF) and near-infrared spectroscopy (NIR). In this work, the samples in the test were obtained from a tungsten dressing plant. It is vital to master the mineral grade for controlling the flotation plant. The XRF parameters were optimised by Monte Carlo simulation, and the XRF and NIR data fusion was discussed. A multivariate statistical method called the least squares support vector machine (LS-SVM) was employed to perform the element-to-mineral conversion. The results show that such data integrations enable on-stream and quantitative identification of slurry mineral contents, especially for scheelite, wolframite, fluorite and calcite, which are essential minerals in tungsten ore beneficiation. This technique can lead to many benefits, such as rapid control of concentrate quality, enhanced recovery and savings in money, time, energy and workforce.A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was used for quantification of four potential genotoxic impurities (PGIs) in the ceritinib active pharmaceutical ingredient. Chromatographic separation was achieved using a YMC-Triart C18 column, with 0.1% formic acid in water as mobile phase A and acetonitrile as mobile phase B in gradient elution mode at a 0.5 mL min-1 flow rate. Quantification of impurities was carried out using triple quadrupole mass detection with electrospray ionization in multiple reaction monitoring mode. The method was fully validated with good linearity over the concentration range of 0.5-5.0 ppm of the ceritinib test concentration for all four PGIs. The correlation coefficient obtained in each case was >0.998. The recoveries were found satisfactory over the range between 83.7 and 107.3% for all selected impurities. The developed method was able to quantitate all four PGIs at a concentration level of 1 ng mL-1 (0.5 ppm with respect to 2 mg mL-1 ceritinib).A novel electrochemical aptasensor for ATP was developed based on an aptamer-embedded configuration-switchable tetrahedral DNA nanostructure (TDN) and the formation of a G-quadruplex. This unique TDN was formed through the self-assembly of four specially designed single-stranded DNA (ssDNA) sequences (S1, S2, S3 and S4). The TDN was immobilized on the surface of a Au electrode through the thiol groups at the 5′-end of S1, S2 and S3. Five edges of the TDN were designed to form a double helix to preserve the structural robustness of the tetrahedron, while the ATP aptamer embedded sequence (S3) was designed to be located at the rest edge. The two terminals of S4 at the same edge were composed of two split G-quadruplex-forming sequences, which were non-complementary to the aptamer. This edge offered the configuration-switchable characteristic of the TDN. In the absence of ATP, the TDN remained in a relaxed state, and the G-quadruplex cannot form due to the large distance between the split G-quadruplex-forming sequences.