A Highly Selective and Sensitive Chemiluminescent Probe for Real‐Time Monitoring of Hydrogen Peroxide in Cells and Animals

Selective and sensitive molecular probes for hydrogen peroxide (H₂O₂), which plays diverse roles in oxidative stress and redox signaling, are urgently needed to investigate the physiological and pathological effects of H₂O₂. A lack of reliable tools for in vivo imaging has hampered the development of H₂O₂ mediated therapeutics. By combining a specific tandem Payne/Dakin reaction with a chemiluminescent scaffold, H₂O₂‐CL‐510 was developed as a highly selective and sensitive probe for detection of H₂O₂ both in vitro and in vivo. A rapid 430‐fold enhancement of chemiluminescence was triggered directly by H₂O₂ without any laser excitation. Arsenic trioxide induced oxidative damage in leukemia was successfully detected. In particular, cerebral ischemia‐reperfusion injury‐induced H₂O₂ fluxes were visualized in rat brains using H₂O₂‐CL‐510 , providing a new chemical tool for real‐time monitoring of H₂O₂ dynamics in living animals.     

Ordered Solid‐State Microstructures of Conjugated Polymers Arising from Solution‐State Aggregation

Controlling the solution‐state aggregation of conjugated polymers for producing specific microstructures remains challenging. Herein, a practical approach is developed to finely tune the solid‐state microstructures through temperature‐controlled solution‐state aggregation and polymer crystallization. High temperature generates significant conformation fluctuation of conjugated backbones in solution, which facilitates the polymer crystallization from solvated aggregates to orderly packed structures. The polymer films deposited at high temperatures exhibit less structural disorders and higher electron mobilities (up to two orders of magnitude) in field‐effect transistors, compared to those deposited at low temperatures. This work provides an effective strategy to tune the solution‐state aggregation to reveal the relationship between solution‐state aggregation and solid‐state microstructures of conjugated polymers.     

An overview on enrichment methods for cell surface proteome profiling

Cell surface proteins are essential for many important biological processes, including cell–cell interactions, signal transduction, and molecular transportation. With the characteristics of low abundance, high hydrophobicity, and high heterogeneity, it is difficult to get a comprehensive view of cell surface proteome by direct analysis. Thus, it is important to selectively enrich the cell surface proteins before liquid chromatography with mass spectrometry analysis. In recent years, a variety of enrichment methods have been developed. Based on the separation mechanism, these methods could be mainly classified into three types. The first type is based on their difference in the physicochemical property, such as size, density, charge, and hydrophobicity. The second one is based on the bimolecular affinity interaction with lectin or antibody. And the third type is based on the chemical covalent coupling to free side groups of surface‐exposed proteins or carbohydrate chains, such as primary amines, carboxyl groups, glycan side chains. In addition, metabolic labeling and enzymatic reaction‐based methods have also been employed to selectively isolate cell surface proteins. In this review, we will provide a comprehensive overview of the enrichment methods for cell surface proteome profiling.     

Simultaneous enantioselective determination of omeprazole,rabeprazole, lansoprazole,and pantoprazole enantiomers in human plasma by chiral liquid chromatography–tandem mass spectrometry

Proton pump inhibitors, including omeprazole, rabeprazole, lansoprazole, and pantoprazole, achieved simultaneous enantioselective determination in the human plasma by chiral liquid chromatography–tandem mass spectrometry. The four corresponding stable isotope‐labeled proton pump inhibitors were adopted as the internal standards. Each enantiomer and the internal standards were extracted with acetonitrile containing 0.1% ammonia, then separated with a Chiralpak IC column (5 µm, 4.6 mm × 150 mm) within 10 min. The mobile phase was composed of acetonitrile–ammonium acetate (10 mM) containing 0.2% acetic acid (50:50, v/v). To quantify all enantiomers, an API 4000 tandem mass spectrometer was used, and multiple reaction monitoring transitions were performed on m/z 360.1→242.1, 384.1→200.1, 370.1→252.1, and 346.1→198.1, respectively. No significant matrix effect was observed for all analytes. The calibration curve for all enantiomers were linear from 1.25 to 2500 ng/mL. The precisions for intra‐ and inter‐run were < 14.2%, and the accuracy fell in the interval of –5.3 to 8.1%. Stability of samples was confirmed under the storage and processing conditions. The developed method was also suitable for separation and determination of ilaprazole enantiomers. The validated method combining the equilibrium dialysis method was applied to the protein binding ratio studies of four pairs proton pump inhibitor enantiomers in human plasma.     

A ternary organic solar cell with 300 nm thick active layer shows over 14% efficiency

In order to meet the requirements for making organic solar cells(OSCs) through solution printing techniques, great efforts have been devoted into developing high performance OSCs with relatively thicker active layers. In this work, a thick-film(300 nm)ternary OSC with a power conversion efficiency of 14.3% is fabricated by introducing phenyl-C_(61)-butyric-acid-methyl ester(PC_(61)BM) into a PBDB-T-2Cl:BTP-4 F host blend. The addition of PC_(61)BM is found to be helpful for improving the hole and electron mobilities, and thus facilitates charge transport as well as suppresses charge recombination in the active layers, leading to the improved efficiencies of OSCs with relatively thicker active layers. Our results demonstrate the feasibility of employing fullerene derivative PC_(61)BM to construct a high-efficiency thick-film ternary device, which would promote the development of thick layer ternary OSCs to fulfill the requirements of future roll to roll production.     

Photo-driven water splitting photoelectrochemical cells by tandem organic dye sensitized solar cells with I−/I3− as redox mediator

Dye-sensitized photoelectrochemical tandem cells have shown the promise for light driven hydrogen production from water owing to the low cost,wide absorption spectra in the visible region and ease to process of their constitutive photoelectrode materials.However,most photo-driven water splitting photoelectrochemical cells driven by organic dye sensitized solar cells exhibit unsatisfactory hydrogen evolution rate,primarily attributed to their poor light capturing ability and low photocurrent performance.Here we present the construction of a tandem system consisting of an organic blue-colored S5 sensitizer-based dyesensitized photoelectrochemical cell(DSPEC) wired in series with three spectral-complemental dyes BTA-2,APP-3 and APP-1 sensitizers-based dye-sensitized solar cell(DSC),respectively.The two spectral-complemental chromophores were used in DSC and DSPEC to ensure that the full solar spectrum could be absorbed as much as possible.The results showed that the photocurrent of tandem device was closely related to the open-circuit voltage(Voc) of sensitized DSC,in which the tandem configuration consisting of S5 based DSPEC and BTA-2 based DSC gave the best photocurrent.On this basis,tandem device with the only light energy and no external applied electrical bias was further constructed of BTA-2 based 2-junction DSC and S5 based DSPEC and obtained a photocurrent of 500 μA cm-2 for hydrogen generation.Furthermore,I-/I3-was used as a redox couple between dye regeneration and O2 production on the surface of Pt-IrO2/WO3.The strategy opens up the application of pure organic dyes in DSC/DSPEC tandem device.     

Understanding energetic disorder in electron-deficient-core-based non-fullerene solar cells

Recent advances in material design for organic solar cells(OSCs) are primarily focused on developing near-infrared nonfullerene acceptors, typically A-DA′D-A type acceptors(where A abbreviates an electron-withdrawing moiety and D, an electron-donor moiety), to achieve high external quantum efficiency while maintaining low voltage loss. However, the charge transport is still constrained by unfavorable molecular conformations, resulting in high energetic disorder and limiting the device performance. Here, a facile design strategy is reported by introducing the "wing"(alkyl chains) at the terminal of the DA′D central core of the A-DA′D-A type acceptor to achieve a favorable and ordered molecular orientation and therefore facilitate charge carrier transport. Benefitting from the reduced disorder, the electron mobilities could be significantly enhanced for the"wing"-containing molecules. By carefully changing the length of alkyl chains, the mobility of acceptor has been tuned to match with that of donor, leading to a minimized charge imbalance factor and a high fill factor(FF). We further provide useful design strategies for highly efficient OSCs with high FF.     

Synthesis of a Hierarchically Porous C/Co3O4 Nanostructure with Boron Doping for Oxygen Evolution Reaction

Fabricating a low‐cost and highly efficient electrocatalyst is of importance for the development of renewable energy devices. In this work, we have synthesized an ultrafine cobalt oxide nanocatalyst (5–10 nm) doped with boron (BC/Co₃O₄) by using a metal–organic framework as a precursor, which exhibits an excellent catalytic activity for oxygen evolution reaction (OER). Owing to the improvement of accessible active sites by boron doping, the synthesized catalyst can reach a current density of 10 mA cm^?2 at 1.54 V with a low overpotential of 310 mV, superior than those of commercial RuO₂ and N‐doped C/Co₃O₄. This work provides a facile way to develop highly efficient catalysts for electrochemical reactions.     

Design of a quad-stable piezoelectric energy harvester capable of programming the coordinates of equilibrium points

In this study, a novel quad-stable energy harvester (QEH) is developed, in which its coordinates of equilibrium points can be user-defined like programming. This programmable feature distinguishes the proposed QEH from all reported magnet-type or buckling-type vibration energy harvesters. It has the advantage that it is easy to develop a high-performance QEH by appropriately programming these coordinate points and customizing a personalized QEH for different vibration environments. The dynamic model is established by the Ritz method and the Lagrange equation. The analytical steady periodic response is obtained by the average method. When the excitation acceleration is 2 m/s², the peak power is 575 μW at 8.5 Hz. Also, the influence of the coordinate arrangement of the equilibrium points on the energy harvesting performance is studied. A formula that can quickly determine the equilibrium point coordinates is given, and the QEH designed according to this formula has superior performance. At last, the performance of the designed QEH is compared with other reported vibration energy harvesters. It shows that the QEH has a high average output power (287 μW), high normalized power density (59.8 μW/cm³/g²), and wide operating frequency range (8.4 Hz) among these harvesters.

     

The impact of the global and local awareness diffusion on epidemic transmission considering the heterogeneity of individual influences

In this paper, we propose a coupled awareness—epidemic spreading model considering the heterogeneity of individual influences, which aims to explore the interaction between awareness diffusion and epidemic transmission. The considered heterogeneities of individual influences are threefold: the heterogeneity of individual influences in the information layer, the heterogeneity of individual influences in the epidemic layer and the heterogeneity of individual behavioral responses to epidemics. In addition, the individuals’ receptive preference for information and the impacts of individuals’ perceived local awareness ratio and individuals’ perceived epidemic severity on self-protective behavior are included. The epidemic threshold is theoretically established by the microscopic Markov chain approach and the mean-field approach. Results indicate that the critical local and global awareness ratios have two-stage effects on the epidemic threshold. Besides, either the heterogeneity of individual influences in the information layer or the strength of individuals’ responses to epidemics can influence the epidemic threshold with a nonlinear way. However, the heterogeneity of individual influences in the epidemic layer has few effect on the epidemic threshold, but can affects the magnitude of the final infected density.