Latest ArticlesThe catalytic performance of light-derived CO2 reduction with H2O is strongly dependent on the separation efficiency of photogenerated carriers. Herein, the direct Z-scheme catalysts (g-C3N4/3DOM-WO3) of graphitic carbon nitride (g-C3N4) nanosheets decorated three-dimensional ordered macroporous WO3 (3DOM-WO3) were successfully fabricated by using the in-situ colloidal crystal template method. The slow light effect of 3DOM-WO3 photonic crystals expands the absorption of visible light and improves the utilization of light energy. The Z-scheme structure of g-C3N4/3DOM-WO3 catalysts is able to upgrade the separation efficiency of photogenerated electron-hole pairs. The g-C3N4/3DOM-WO3 photocatalyst, whose formation rate of CO product is 48.7 μmol g−1 h−1, exhibits the excellent catalytic activity for CO2 reduction. The transfer pathway of stimulated electrons over the g-C3N4/3DOM-WO3 photocatalyst is proposed and discussed. The present approach provides unique insights into the rational development of high-performance photochemical systems for efficient CO2 reduction into valuable carbon-containing chemicals and energy fuels.
Exploring platinum group metal-free electrocatalysts with superior catalytic performance and favorable durability for oxygen reduction reaction is a remaining bottleneck in process of developing sustainable techniques in energy storage and conversion. Herein, a hierarchical porous single atomic Fe electrocatalyst (Fe/Z8-E-C) is rationally designed and synthesized via acid etching, calcination, adsorption of Fe precursor and recalcination processes. This unique electrocatalyst Fe/Z8-E-C shows excellent oxygen reduction performance with a half-wave potential of 0.89 V in 0.1 mol/L KOH, 30 mV superior to that of commercial Pt/C (0.86 V), which is also significantly higher than that of typical Fe-doped ZIF-8 derived carbon nanoparticles (Fe/Z8-C) with a half-wave potential of 0.84 V. Furthermore, Fe/Z8-E-C-based Zn-air battery exhibits greatly enhanced peak power density and specific capacity than those of original Fe/Z8-C, verifying the remarkable performance and practicability of this specially designed hierarchical structure due to its efficient utilization of the active sites and rapid mass transfer. This present work proposes a new method to rationally synthesize single atom electrocatalysts loaded on hierarchical porous frame materials for catalysis and energy conversion.
To obtain a high-performance heterogeneous photo-catalyst, herein, the hetero-structured ZnIn2S4-NiO@MOF (ZNM) nano-sheets are designed and prepared by partial pyrolysis of nickel-based MOFs (Ni-MOF) combined with the low-temperature solvo-thermal method. The results indicate that the NiO nanoparticles, produced by partial pyrolysis of the Ni-MOF, have a high density of the surface active sites with limited aggregation, which act as a co-catalyst to capture photo-induced charge carriers. In addition, the morphology and structure of Ni-MOF nano-sheets were preserved in ZNM, which is beneficial to the reduction of the conduction barrier for the photo generated electron-hole pairs. With the synergetic advantages of co-catalyst and unique two-dimensional hetero-structure, ZNM nano-sheets exhibited significantly improved activity for photo-catalytic hydrogen production.
Cysteine is well-known to be an important biothiol and related to many diseases. However, the in vivo detection of endogenous cysteine still suffers from lacking small-molecule fluorophores with both excitation and emission in the near-infrared (650-900 nm)/shortwave-infrared region. Herein, we report a molecular engineering strategy for shortwave infrared (SWIR, 900-1700 nm) sensing of cysteine, which integrated an excited-state intermolecular proton transfer (ESIPT) building block into the intramolecular charge transfer (ICT) scaffold. The obtained novel fluorophore SH-OH displays a maximum absorption at the NIR region, and emission at the SWIR region. We introduce the cysteine-recognition moiety to SH-OH structure, and demonstrate sensing of endogenous cysteine in living animals, using the SWIR emission as a reliable off-on fluorescence signal. This fluorophore design strategy of cooperation of ICT and ESIPT processes expands the in vivo sensing toolbox for accurate analysis in clinical applications.
The undesirable enzymatic activity of nanozymes under near neutral pH condition and the traditional single signal output always restrict the analytical application of nanozyme-based biosensors. Herein, graphitic carbon nitride nanosheets supported palladium nanosheets composite (Pd/g-C3N4) with both oxidase-like activity and fluorescent property is synthesized. Notably, Pd/g-C3N4 exhibits enhanced oxidase-like activity compared to Pd NSs under pH 7.4. By combining Pd/g-C3N4 with o-phenylenediamine (OPD), a ratiometric fluorescence assay for acetylcholinesterase (AChE) activity detection is developed. Pd/g-C3N4 can catalyze oxidation of nonfluorescent OPD to fluorescent oxidized OPD (oxOPD, Em = 565 nm), which can quench fluorescence of g-C3N4 supporter (Em = 441 nm) through fluorescence resonance energy transfer (FRET). However, in presence of AChE, acetylthiocholine can be hydrolyzed into thiocholine, which will block the oxidase-like activity of Pd/g-C3N4 and then hamper the FRET process. This ratiometric fluorescence assay is also viable to screen AChE inhibitor. This work will guide design of ratiometric fluorescence assay based on nanozymes with improved enzymatic activity.
Graphene-based sponge is a novel hemostatic material prepared by chemical cross-link of graphene oxide. It has a fast fluid absorption capacity to quickly absorb blood from wounds, activate clotting pathways, and achieve rapid hemostasis. In addition, graphene-based sponge is also a good platform carrier. It can be prepared by organic cross-linking, compounding with inorganic clay, and adding bioactive factors to enhance coagulation stimulation. By these methods, the hemostatic performance of the sponge is further improved, which shows great potential for application in the field of trauma hemostasis. This article reviews the research progress of graphene-based sponges from three different preparation strategies (organic cross-linking, inorganic compounding and adding bioactive factor), summarizes their hemostatic mechanisms, and prospects the development of graphene-based hemostatic sponges.
Current resolved structures of GPCRs and G protein complexes provided important insights into G protein activation. However, the binding or dissociation of GPCRs with G protein is instantaneous and highly dynamic in the intracellular environment. The conformational dynamic of G protein still needs to be addressed. In this study, we applied 19F solution NMR spectroscopy to monitor the conformational changes of G protein upon interact with detergent mimicking membrane and receptor. Our results show that there are two states equilibria in the Gα in apo states. The interaction of Gα with detergents will accelerate this conformational transformation and induce a state that tends to bind to GPCRs. Finally, the Gα proteins presented a fully activation state when they coupled to GPCRs.
Chemiluminescence immunoassay (CLIA) has always been a great challenge in detecting cardiac troponin I (cTnI) in whole blood samples without centrifugation because of the interference of red blood cells and low sensitivity. In this study, the antigens and erythrocytes in the blood were captured by the antibodies immobilized on the magnetic particles, recognized by another biotin-conjugated cTnI antibody and detected by streptavidin/acridine aster-conjugated polychloromethylstyrene microspheres (PCMS). After magnetic separation, the supernatant was transferred and measured. No significant difference was noted between the cTnI concentrations of the serum samples, plasma samples and whole blood. The prepared PCMS provided more functional areas to conjugate streptavidin and acridinium ester, so the immunoassay has highly sensitive, the limits of blank at 0.012 ng/mL, and functional sensitivity at 0.019 ng/mL with a CV of 20%, and 0.058 ng/mL with a CV of 10%. Total precision of any sample type ranged from 2.62%~5.67%. The assay was linear over the studied range of 0.01-50.00 ng/mL, and no hook effect was found when cTnI concentrations reached 1900 ng/mL. No significant interference was noted with the potential endogenous interfering substances. Compared with the commercial kit (Abbott assay kit), the correlation coefficient was 0.9859. A washing-free CLIA was established for the rapid detection of cTnI in human whole blood, using erythrocyte capture antibodies-conjugated magnetic nanoparticles for eliminating the influence of erythrocytes and PCMS for signal amplification, which showed great potential in clinical application.
Carbon dots (CDs), because of their unique properties, are being rapidly developed as important luminescent materials for imaging, sensing, and use in photonic devices. However, most of the reported fundamental properties of the CDs are results of investigations conducted in the solution state, which may be completely different from those conducted in the solid state. In this work, we study the luminescence properties, photostability, and the dynamics of CDs in different matrix environments, from ensemble to the single-particle level. We observed that the properties associated with the emission centers and photostability of CDs were extremely sensitive to the local chemical environment. A better understanding of the dependence of the spectroscopic properties of CDs on the complex local chemical environment is an important step toward finding new ways of controlling the optical properties of CDs and optimizing their use in various applications.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
