Latest ArticlesImproving the surface atoms utilization efficiency of catalysts is extremely important for large-scale H2 production by electrochemical water splitting, but it remains a great challenge. Herein, we reported two kinds of MoO3-polyoxometalate hybrid nanobelt superstructures (MoO3-POM HNSs, POM= PW12O40 and SiW12O40) using a simple hydrothermal method. Such superstructure with highly uniform nanoparticles as building blocks can expose more surface atoms and emanate increased specific surface area. The incorporated POMs generated abundant oxygen vacancies, improved the electronic mobility, and modulated the surface electronic structure of MoO3, allowing to optimize the H* adsorption/desorption and dehydrogenation kinetics of catalyst. Notably, the as-prepared MoO3-PW12O40 HNSs electrodes not only displayed the low overpotentials of 108 mV at 10 mA/cm2 current density in 0.5 mol/L H2SO4 electrolyte but also displayed excellent long-term stability. The hydrogen evolution reaction (HER) performance of MoO3-POM superstructures is significantly better than that of corresponding bulk materials MoO3@PW12O40 and MoO3@SiW12O40, and the overpotentials are about 8.3 and 4.9 times lower than that of single MoO3. This work opens an avenue for designing highly surface-exposed catalysts for electrocatalytic H2 production and other electrochemical applications.
Accurate determination of lung cancer margins at the molecular level is of great significance to determine the optimal extent of resection during surgical operation and reduce the risk of postoperative recurrence. In this study, internal extractive electrospray ionization mass spectrometry (iEESI-MS) was used to trace potential molecular tumor margins in lung cancer tissue. Molecular differential model for the determination of lung cancer tumor margin was established via partial least-squares discriminant analysis (PLS-DA) of iEESI-MS data collected from lung tissue pieces within cancer tumor area and iEESI-MS data collected from lung tissue pieces outside cancer tumor area. Proof-of-concept data demonstrate that the developed molecular differential model yields ca. 1–2 mm wider potential molecular tumor margin of a lung cancer compared to the conventional histological analysis, showing promising potential of iEESI-MS to increase the accuracy of tumor margins determination and lower risk of lung cancer postoperative recurrence. Furthermore, our results revealed that creatine and taurine showed positive correlations with lung cancer.
Semi-heterogeneous photocatalysis has emerged as a powerful and productive platform in organic chemistry, which provides mild and eco-friendly conditions for a diverse range of bond-forming reactions. The synergy of homogeneous catalysts and heterogeneous catalysts inherits their main advantages, such as higher activities, easy separation and superior recyclability. In this review, we summarize the recent advances in recyclable semi-heterogenous protocols for the light promoted bond-forming reactions and identify directions for future research according to the different photocatalysts/metal/redox catalysts involved. Notably, this review is not a comprehensive description of reported literature but aim to highlight and illustrate key concepts, strategies, reaction model, reaction conditions and mechanisms.
Imaging detection of interlinked dual proteases is imperative for precise tumor imaging, which remains challenging due to limited modification position of specific substrate and possible steric hindrance. Herein, we have developed a unimolecular chemiluminescent probe (LGP-CL) tandemly activated by two proteases interlinked with liver cancer to achieve precise tumor imaging. Probe LGP-CL consists of a phenoxy-dioxetane scaffold caged by a tripeptide substrate (LGP, leucine-glycine-proline) as the sensing layer, which can be cleaved sequentially by aminopeptidase N (APN) and dipeptidyl peptidase Ⅳ (DPPIV) to turn on a strong chemiluminescent signal, and silenced by specific inhibitor of each enzyme, which accounts for an integrated logic gate (AND, OR and INHIBIT). The successful cleavage of dual proteases on the metabolic site depends on the proper structure of the tripeptide substrate, as confirmed by two probes design. Probe LGP-CL (LGP as the substrate) enables the excellent "dual-lock-dual-key" fit with a 382-fold enhancement of chemiluminescent emission while no obvious signal is observed by using GPL-CL (GPL as the substrate). By virtue of its rapid response (several minutes), high sensitivity and good cell viability, probe LGP-CL has been utilized to evaluate upregulated levels of proteases in vitro and in living systems, especially to distinguish liver tumor cells (HepG2) from others (LO2, MCF-7, MCF-10a and RAW264.7). Overall, the newly developed CL probe may facilitate rapid investigation into the role played by proteases in liver diseases, enabling timely selection appropriate treatment. Therefore, our work not only sheds light on the rational design of optical probes for dual protease imaging, but provides a promising tool for clinical diagnosis and even drug discovery.
Ultrasensitive detection of nucleic acids is of great significance for precision medicine. Digital polymerase chain reaction (dPCR) is the most sensitive method but requires sophisticated and expensive instruments and a long reaction time. Digital PCR-free technologies, which mean the digital assay not relying on thermal cycling to amplify the signal for quantitative detection of nucleic acids at the single-molecule level, include the digital isothermal amplification techniques (dIATs) and the digital clustered regularly interspaced short palindromic repeats (CRISPR) technologies. They combine the advantages of dPCR and IATs, which could be fast and simple, enabling absolute quantification of nucleic acids at a single-molecule level with minimum instrument, representing the next-generation molecular diagnostic technology. Herein, we systematically summarized the strategies and applications of various dIATs, including the digital loop-mediated isothermal amplification (dLAMP), the digital recombinase polymerase amplification (dRPA), the digital rolling circle amplification (dRCA), the digital nucleic acid sequence-based amplification (dNASBA) and the digital multiple displacement amplification (dMDA), and evaluated the pros and cons of each method. The emerging digital CRISPR technologies, including the detection mechanism of CRISPR and the various strategies for signal amplification, are also introduced comprehensively in this review. The current challenges as well as the future perspectives of the digital PCR-free technology were discussed.
Solid-state batteries (SSBs) with high-capacity Si anodes have been regarded as one of the most promising candidates to meet the large scale energy storage and electrical vehicles due to its intrinsic safety and potential high energy density. However, Si suffers from poor electrical conductivity and huge volume change and particles fracture during lithiaiotn and delithiation, which induces low practical energy density. In addition, the SSBs are often operated at high temperature due to the poor physical contact and huge resistance between Si and solid-state electrolyte (SSE). To improve the bulk electronic/ionic conductivity of Si and its interfacial compatibility with SSE, herein, a binder free and self-supporting Si/C film was developed. The monolithic carbon not only enhance the electric conductivity but also release huge stress during lithiation and delithiation. In addition, paired with the flexible and soft poly(vinylidene fluoride)-co-hexafluoropropylene (PVDF-HFP) and Li1.3Al0.3Ti1.7(PO4)3 (LATP) solid-state electrolyte, a LiF-rich and electrochemical stable solid-electrolyte interphase (SEI) layer is in-situ engineered. The fast bulk and interfacial ionic transportation as well as the mechanical integrity of MSi enable high performance SSBs at room temperature. As a result, high specific capacity of 2137 mAh/g with an initial Coulombic efficiency of 83.2% is obtained at a rate of 0.5 A/g. Even at a high rate of 3 A/g, the specific capacity is 1793 mAh/g. At a rate of 1 A/g, the Si/C anode delivers a long cycling performance over 500 cycles while maintains a capacity of 1135 mAh/g. This work provides a new strategy that combines charge transfer kinetics and interfacial chemistry design toward high energy density Si-based SSBs.
Acute lung injury (ALI) was characterized by excessive reactive oxygen species (ROS) levels and inflammatory response in the lung. Scavenging ROS could inhibit the excessive inflammatory response, further treating ALI. Herein, we designed a novel nanozyme (P@Co) comprised of polydopamine (PDA) nanoparticles (NPs) loading with ultra-small Co, combining with near infrared (NIR) irradiation, which could efficiently scavenge intracellular ROS and suppress inflammatory responses against ALI. For lipopolysaccharide (LPS) induced macrophages, P@Co + NIR presented excellent antioxidant and anti-inflammatory capacities through lowering intracellular ROS levels, decreasing the expression levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) as well as inducing macrophage M2 directional polarization. Significantly, it displayed the outstanding activities of lowering acute lung inflammation, relieving diffuse alveolar damage, and up-regulating heat shock protein 70 (HSP70) expression, resulting in synergistic enhanced ALI therapy effect. It offers a novel strategy for the clinical treatment of ROS related diseases.