- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Modulating Protein-Protein Interactions with Visible-Light Responsive Peptide Backbone Photoswitches
摘要： Life relies on a myriad of carefully orchestrated processes, in which proteins and their direct interplay ultimately determine cellular function and disease. Modulation of these complex cross-talks has recently attracted attention, even as a novel therapeutic strategy. Here, we describe the synthesis and characterization of two visible-light responsive peptide backbone photoswitches based on azobenzene derivatives to exert optical control over protein-protein interactions (PPI). Our novel peptidomimetics undergo fast isomerization and reversibility with low photochemical fatigue under alternatively blue/green-light irradiation cycles. Both bind in the nanomolar rage to the protein of interest. Importantly, our best peptidomimetic displays a clear difference between isomers in its protein-binding capacity and, in turn, in its potential to inhibit enzymatic activity via PPI disruption. In addition, crystal structure determination, docking and MD calculations give a molecular interpretation and open new avenues in the design and synthesis of future photoswitchable PPI modulators.
关键词： protein-protein interactions,photopharmacology,visible-light irradiation,azobenzene,photoswitches
更新于2025-11-21 11:20:42
-
Effect of conduction band potential on cocatalyst-free plasmonic H <sub/>2</sub> evolution over Au loaded on Sr <sup>2+</sup> -doped CeO <sub/>2</sub>
摘要： There is little information on the effect of the conduction band (CB) position on plasmonic hydrogen (H2) formation under visible light irradiation over gold (Au) nanoparticles supported on semiconductors because there were no appropriate materials for which the CB position gradually changes. In this study, we analyzed the flatband potential of strontium ion (Sr2+)-doped cerium(IV) oxide (CeO2:Sr) and found that the CB position gradually shifted negatively from +0.031 V to ?1.49 V vs. NHE with an increase in the Sr2+ mole fraction. Plasmonic photocatalysts consisting of Au nanoparticles, CeO2:Sr and a platinum (Pt) cocatalyst were prepared and characterized by using X-ray diffraction, UV-vis spectroscopy, and transmission electron spectroscopy. Photocatalytic reaction under visible light irradiation revealed that H2 was produced over Au nanoparticles supported on CeO2:Sr having the CB potential of ?0.61 V vs. NHE and that the negative limit of the CB position for electron injection from Au nanoparticles existed between ?0.61 V and ?1.49 V vs. NHE. We found that Au/CeO2:Sr plasmonic photocatalysts also produced H2 without the aid of a Pt cocatalyst due to the sufficiently negative potential of electrons injected into the CB of CeO2:Sr.
关键词： hydrogen evolution,visible light irradiation,gold nanoparticles,plasmonic photocatalysts,strontium-doped cerium oxide
更新于2025-11-19 16:51:07
-
Visible-light-triggered generation of persistent radical anions from perylenediimides: A substituent effect and potential application in photocatalytic reduction of Ag+
摘要： Three perylenediimide derivatives were reduced to their persistent radical anions in N-methyl-2-pyrrolidone (NMP) under ambient conditions by a visible light photoinduced electron transfer (PET). UV?vis and electron paramagnetic resonance (EPR) measurements were carried out to confirm the formation of radicals. The relationships between molecular structure, electrochemical property, phototransformation kinetics, and air stability of radical anions were investigated by the introduction of pyrimidine rings at the core position and fluoroalkylation substituents at the imide position. This study reveals that the electron-deficient pyrimidine rings and electron-withdrawing fluoroalkylation substituents can effectively enhance the phototransformation rate and the radical stability at ambient conditions. The effects of solvents and illuminance levels on the photoinduced reduction of perylenediimides were also studied. A photocatalytic reduction of Ag+ was successfully carried out using the perylenediimide with pyrimidine and fluoroalkylation substituents as catalyst upon irradiation with visible light.
关键词： Photocatalytic reduction,Perylene diimide derivative,Silver ion,Persistent radical anion,Visible light irradiation
更新于2025-11-14 17:03:37
-
Construction of Pt-decorated g-C3N4/Bi2WO6 Z-scheme composite with superior solar photocatalytic activity toward rhodamine B degradation
摘要： Highly efficient visible-light-driven Pt-decorated g-C3N4/Bi2WO6 hybrid photocatalysts were successfully prepared via a photodeposition method. The microstructures and optical properties of the prepared samples were characterized by transient photocurrent experiments, X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), UV-vis diffused reflectance spectra (DRS), photoluminescence (PL), electron spin resonance (ESR) spectroscopy and X-ray photoelectron spectroscopy (XPS) techniques. FESEM and TEM images show that metallic Pt particles disperse on the surface of g-C3N4/Bi2WO6 hybrid. Pt-decorated g-C3N4/Bi2WO6 compsites exhibited excellent DRS attribute to the surface plasmonic resonance (SPR) of Pt particles and g-C3N4/Bi2WO6. The PL results verified that the suitable band potential of g-C3N4 and Bi2WO6 for construction of Z-type photocatalytic system. In the photocatalytic experiment, results showed that Pt(1%)-g-C3N4/Bi2WO6 photocatalysts displayed higher photocatalytic activity than either pure g-C3N4 or Bi2WO6 for the degradation of Rhodamine B (RhB). Additionally, the free-radical trapping experiments and ESR disclose that the hole (h+), superoxide radical (·O2-) and hydroxyl radical (·OH) acted as reactive species. Based on above, a possible plasmonic Z-scheme mechanism for organics degradation over Pt-decorated g-C3N4/Bi2WO6 was proposed.
关键词： g-C3N4/Bi2WO6,Visible light irradiation,Z-scheme heterojunction,Pt-decorated
更新于2025-09-23 15:23:52
-
Microwave Hydrothermal Synthesis of In <sub/>2</sub> O <sub/>3</sub> -ZnO Nanocomposites and Their Enhanced Photoelectrochemical Properties
摘要： Indium oxide (In2O3) doped zinc oxide (ZnO) nanocomposites were successfully synthesized through a facile microwave hydrothermal method. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), N2 adsorption–desorption isotherms (BET) and UV-Vis diffuse reflectance spectroscopy. The morphology of In2O3-ZnO composites was observed to be like flowers, and the diameter of particles constituting the porous petal was about 30 nm. The photoelectrocatalytic test results showed that the photoelectrocatalytic methylene blue (MB) degradation efficiency using In2O3-ZnO nanocomposites as photocatalysts under visible light irradiation and a certain voltage could reached above 95.3% after 60 min, much higher than that of In2O3 particles and ZnO particles. The enhanced photoelectrocatalytic activity was attributed to the doping of In2O3 and applied voltage, which beneficially reduced the recombination of electrons and holes in the photoelectrocatalytic process, therefore, it promoted the production of active species (?OH and ?O2-).
关键词： photoelectrochemical properties,visible light irradiation,methylene blue degradation,In2O3-ZnO nanocomposites,microwave hydrothermal synthesis
更新于2025-09-23 15:22:29
-
3D graphene aerogels/Sb2WO6 hybrid with enhanced photocatalytic activity under UV- and visible-light irradiation
摘要： A novel ultraviolet (UV)- and visible-light-active 3D graphene aerogels (3DGA)/Sb2WO6 hybrid photocatalyst was prepared by electrostatic self-assembly (ESSA) method. The photocatalytic activity of the 3DGA/Sb2WO6 hybrid was studied by monitoring the change in the concentration of methyl orange (MO) under UV-light and visible-light irradiation. The results demonstrated that the as-prepared hybrid exhibited significantly enhanced efficiency for the photodegradation of MO in comparison with pure Sb2WO6. This was ascribed to the efficient separation of the photogenerated electrons (e–) and holes (h+) with the aid of 3DGA as well as the generated reactive superoxide radical anions (O2(cid:129)–). Moreover, the 3DGA/Sb2WO6 hybrid exhibited high recyclability, because the highly hydrophobic 3DGA in the hybrid was very advantageous to the separation of the hybrid photocatalyst from the MO solutions.
关键词： 3D graphene aerogels,Sb2WO6,Electrostatic self-assembly,Hybrid photocatalyst,Visible-light irradiation
更新于2025-09-23 15:21:21
-
Light-Triggered Reversible Self-Engulfing of Janus Nanoparticles
摘要： Block copolymers containing azobenzene liquid crystalline (LC) mesogen are used to prepare snowman-like Janus nanoparticles (NPs) by emulsion solvent evaporation. The azobenzene-containing poly(methacrylate) (PMAAz) head of the Janus NPs is in the smectic LC phase with ordered stripes, which becomes amorphous and enlarged due to trans/cis transformation under UV irradiation. The expanded PMAAz can consequently engulf the other head. The self-engulfed NPs can recover to their original state in both shape and LC state via visible-light irradiation. This strategy is promising for programmable load and release of different payloads by remote trigger using light.
关键词： emulsion solvent evaporation,azobenzene,liquid crystalline,Block copolymers,Janus nanoparticles,programmable load and release,UV irradiation,visible-light irradiation
更新于2025-09-23 15:21:01
-
Visible-Light-Mediated Photoredox-Catalyzed Regio- and Stereoselective Chlorosulfonylation of Alkynes
摘要： Herein, a one-step chlorosulfonylation of alkynes via a photocatalytic redox process is described. A variety of commercially available sulfonyl chlorides can be applied for the generation of sulfonyl radical species under visible-light irradiation. Regio- and stereoselective addition of the sulfonyl radical and chloride leads to the e?cient formation of (E)-selective β-chlorovinyl sulfones from a broad range of terminal and internal alkynes. The reported method represents an operationally simple and mild way to furnish vinyl sulfones.
关键词： photoredox catalysis,vinyl sulfones,chlorosulfonylation,alkynes,visible-light irradiation
更新于2025-09-23 15:21:01
-
Glucose Induced Formation of Oxygen Vacancy and Bi-Metal Co-modified Bi5O7Br Nanotubes for efficient Performance Photocatalysis
摘要： Here, we prepared Bi metal modified defective-Bi5O7Br nanotubes (Bi/Bi5O7Br-OV) by hydrothermal synthesis to be an efficient photocatalyst. The density function theory (DFT) revealed that oxygen vacancies in Bi5O7Br could form an intermediate level, which could allow electron transfer to new intermediate level, and finally move to the conduction band. The Bi/Bi5O7Br-OV nanotubes demonstrate superior photocatalytic degradation of phenol, showing 3 times higher than that of pristine Bi5O7Br. The defects and Bi endow Bi5O7Br nanotubes with abundant active sites and improve the solar absorption. The increased and more dispersed charge density allow enhanced electronic conductivity and the separation of photogenerated carriers. Furthermore, more ·OH radicals are generated during photochemical reaction, which is beneficial in improving the photocatalytic performance. This work will play significant roles and create opportunities in modifying Bi-based materials for promoting photocatalysis.
关键词： photodegradation,bismuth oxybromide,water treatment,visible light irradiation
更新于2025-09-19 17:15:36
-
pH-Controlled photocatalytic abatement of RhB by an FeWO <sub/>4</sub> /BiPO <sub/>4</sub> p–n heterojunction under visible light irradiation
摘要： A novel p–n heterostructure of an FeWO4/BiPO4 nanocomposite was designed and synthesized through a simple hydrothermal method. Among all the nanocomposites prepared with different weight percentages of FeWO4, 30% FeWO4/BiPO4 (S3) showed the highest photocatalytic performance for the degradation of Rhodamine B and tetracycline under visible light irradiation. The degradation efficiency of RhB for the S3 sample was 87% under neutral conditions within 300 min but interestingly, at pH 3, 99% degradation efficiency was observed within 30 min with good recyclability. The enhanced photocatalytic performance should be due to the maximum electron–hole pair decoupling efficiency of the S3 catalyst. The mineralization of RhB during the catalytic process was detected by GC-MS. Consequently, based on the experimental results, a possible photocatalytic mechanism over the FeWO4/BiPO4 composite was anticipated, which indicated the substantial potential of the composite for the treatment of textile and pharmaceutical wastewater.
关键词： p–n heterojunction,Rhodamine B,tetracycline,visible light irradiation,FeWO4/BiPO4,photocatalytic degradation
更新于2025-09-16 10:30:52