Onealholck2040

Droplet-based microfluidic systems offer a high potential for miniaturization and automation. Therefore, they are becoming an increasingly important tool in analytical chemistry, biosciences, and medicine. Heterogeneous assays commonly utilize magnetic beads as a solid phase. However, the sensitivity of state of the art microfluidic systems is limited by the high bead concentrations required for efficient extraction across the water-oil interface. Furthermore, current systems suffer from a lack of technical solutions for sequential measurements of multiple samples, limiting their throughput and capacity for automation. Taking advantage of the different wetting properties of hydrophilic and hydrophobic areas in the channels, we improve the extraction efficiency of magnetic beads from aqueous nanoliter-sized droplets by 2 orders of magnitude to the low μg/mL range. Furthermore, the introduction of a switchable magnetic trap enables repetitive capture and release of magnetic particles for sequential analysis of multiple samples, enhancing the throughput. In comparison to conventional ELISA-based sandwich immunoassays on microtiter plates, our microfluidic setup offers a 25-50-fold reduction of sample and reagent consumption with up to 50 technical replicates per sample. The enhanced sensitivity and throughput of this system open avenues for the development of automated detection of biomolecules at the nanoliter scale.We report the development of azoreductase-responsive prodrug, AP-N=N-Cy, in which the precursor compound AP, a readily available podophyllotoxin derivative, is linked with a NIR fluorophore (Cy) via a multifunctional azobenzene group. This type of azo-based prodrug can not only serve as an azoreductase-responsive NIR probe to real-time tracking of the drug delivery process, but also a delivery platform for anticancer compound (AdP). We have shown that the cleavage of multifunctional azobenzene group in AP-N=N-Cy was only occurred in the presence of azoreductase which specifically secrete in colon, resulting in the directly release of AdP through an in situ modification of a phenylamino group on the precursor AP. Moreover, the introduction of azobenzene group endows the prodrug with an unique fluorescence "off-on" property, and served as a switch to "turn on" the fluorescence of Cy as consequence of a self-elimination reaction while the breakage of azo bond. Such a prodrug can be administered orally, and exhibit high stability and low toxicity before arriving at colon. In view of the synchronism of drug release and fluorescence "turn on" process, the fluorescence imaging method was utilized to precise trace the drug delivery in vitro, ex vivo and in vivo. Distinguishingly, the biodistribution of AdP and Cy in various tissues were further precisely mapped at the molecular level using imaging mass spectrometry . To the best of our knowledge, this is the first time that the in vivo real-time precise tracking of colon-specific drug releases and biodistribution was reported via a multimodal imaging method.The development of active, durable, and nonprecious electrocatalysts for hydrogen electrochemistry is highly desirable but challenging. In this work, we design and fabricate a novel interface catalyst of Ni and Co2N (Ni/Co2N) for hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR). selleck products The Ni/Co2N interfacial catalysts not only achieve a current density of -10.0 mA cm-2 with an overpotential of 16.2 mV for HER but also provide a HOR current density of 2.35 mA cm-2 at 0.1 V vs reversible hydrogen electrode (RHE). Furthermore, the electrode couple made of the Ni/Co2N interfacial catalysts requires only a cell voltage of 1.57 V to gain a current density of 10 mA cm-2 for overall water splitting. Hybridizations in the three elements of Ni-3d, N-2p, and Co-3d result in charge transfer in the interfacial junction of the Ni and Co2N materials. Our density functional theory calculations show that both the interfacial N and Co sites of Ni/Co2N prefer to hydrogen adsorption in the hydrogen catalytic activities. This study provides a new approach for the construction of multifunctional catalysts for hydrogen electrochemistry.Conductive hydrogenated silicon carbide (SiCxH) is discovered as a promising hydrogenation material for tunnel oxide passivating contacts (TOPCon) solar cells. The proposed SiCxH layer enables a good passivation quality and features a good electrical conductivity, which eliminates the need of etching back of SiNxH and indium tin oxide (ITO)/Ag deposition for metallization and reduces the number of process steps. The SiCxH is deposited by hot wire chemical vapor deposition (HWCVD) and the filament temperature (Tf) during deposition is systematically investigated. Via tuning the SiCxH layer, implied open-circuit voltages (iVoc) up to 742±0.5 mV and a contact resistivity (ρc) of 21.1±5.4 mΩ·cm2 is achieved using SiCxH on top of poly-Si(n)/SiOx/c-Si(n) stack at Tf of 2000℃. Electrochemical Capacitance-Voltage (ECV) and Secondary Ion Mass Spectrometry (SIMS) measurements were conducted to investigate the passivation mechanism. Results show that the hydrogenation at the SiOx/c-Si(n) interface is responsible for the high passivation quality. To assess its validity, the TOPCon stack was incorporated as rear electron selective-contact in a proof-of-concept n-type solar cells featuring ITO/a-SiH(p)/a-SiH(i) as front hole selective-contact, which demonstrates a conversion efficiency up to 21.4%, a noticeable open-circuit voltage (Voc) of 724 mV and a fill factor (FF) of 80%.Improving the antibacterial activity of nanomaterials and avoiding the use of H2O2 are vital for biosecurity and public health. In this work, novel Co4S3/Co(OH)2 hybrid nanotubes (HNTs) for the first time were successfully synthesized through the control of Na2S treatment of Co(CO3)0.35Cl0.20(OH)1.10 precursor. On the basis of Kirkendall effect, acicular precursor was vulcanized to form Co4S3/Co(OH)2 HNTs that possess great properties including favorable storage ability and ideal stability. By tailoring the composition and structure, Co4S3/Co(OH)2 HNTs were found to have profound oxidase-like catalytic activities. When pH = 3 precursor was treated with 900 mg of Na2S, Co4S3/Co(OH)2 HNTs exhibit superior performance. Owing to the outstanding oxidase-like activity, Co4S3/Co(OH)2 HNTs can eliminate Escherichia coli, Pseudomonas aeruginosa, Staphylococcus sciuri, and Bacillus without the help of H2O2. It turned out that the sterilization ability came from the superoxide anion radical generated by Co4S3/Co(OH)2 HNTs.