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Spacer engineering in nanoparticle–peptide conjugates boosts targeting specificity for tumor-associated antigens
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Synthesis of micrometre-thick oriented 2D covalent organic framework films by a kinetic polymerization pathway
No full textDespite advances in the field of 2D polymerization, the synthesis of high-quality, micrometre-thick films of oriented 2D covalent organic frameworks (COFs) remains challenging. Conventional approaches focusing on thermodynamic control of the polymerization pathway face a detrimental trade-off between orientation and thickness. Here we describe a straightforward method for preparing imine-linked 2D COF films with a near-perfect face-on orientation by leveraging kinetically trapped amorphous 3D covalent adaptable network (CAN) intermediates. These off-pathway intermediates are generated as coatings through solution casting, during which the CANs spontaneously align to relax tensile stresses induced by solvent evaporation. A subsequent lift-off process, followed by an amorphous-to-crystalline transformation under solvothermal conditions, converts the 3D-oriented polymer networks into thermodynamically stable, porous and free-standing 2D COF films. This versatile kinetic trapping strategy is suitable for a range of building blocks and network topologies, constituting a convenient synthetic tool for accessing high-quality, robust, large-area 2D COF films with a strongly aligned polycrystalline structure
Enhancing zinc-ion energy storage: impact of MOF-5 derived carbonization temperature on performance
No full textWe report the carbonization of metal–organic framework-5 (MOF-5) at various temperatures to investigate the correlation between physicochemical properties and electrochemical performance in zinc-ion energy storage. The sample carbonized at 1000 °C exhibits the highest specific capacitance (268.93 F g−1), energy density (166.9 W h kg−1), and power density (9234 W kg−1), attributed to increased porosity, enhanced graphitization, and reduced charge transfer resistance. This simultaneous achievement of high energy and power densities underscores the potential of carbonized MOF-5 (CMOF-5) as a high-performance nanostructured electrode material for advanced energy storage devices
Mechanical, Antibacterial, and Physico-Chemical Properties of Three Different Polymer-Based Direct Restorative Materials: An In Vitro Study
No full textA novel resin-based bulk-fill restorative material (ST; Stela SDI, Bayswater, Victoria, Australia) has been recently introduced as a self-curing alternative to traditional light-cured composites. Promoted for its unlimited depth of cure, enhanced aesthetics, and unique primer composition, it aims to address challenges associated with amalgam and light-curing composites. Thus, the aim of this in vitro study was to investigate the performance of the new self-curing polymer-based restorative material, ST, compared to two conventional light-cured composites for direct restoration. The study evaluated compressive strength with and without aging, antibacterial activity, mineral deposition in contact with Phosphate-Buffered Saline (PBS) and artificial saliva, porosity, and wettability of ST (Tetric EvoCeram (TE; Ivoclar Vivadent, Schaan, Liechtenstein) and Clearfil Majesty ES-2 (CM; Kuraray Noritake Dental, Tokyo, Japan)). The data was statistically analyzed (α = 0.05) through one-way and two-way analysis of variance (ANOVA). ST demonstrated significantly higher compressive strength than TE and CM at baseline and after aging (p < 0.001), while aging significantly reduced compressive strength across all materials (p < 0.001). Fracture mode analysis revealed brittle fractures for TE and CM, whereas ST fractured in multiple smaller fragments. CM showed the highest void volume and diameter, significantly differing from ST and TE (p < 0.001). Scanning electron microscopy (SEM) analysis revealed cubical-like crystalline formations on ST's surface after 28 days of immersion in PBS and saliva, indicating some level of bioactivity, whereas no changes were observed for TE and CM. Wettability testing showed ST had the lowest contact angle (12.24° ± 2.1°) compared to TE (62.78° ± 4.68°) and CM (64.64° ± 3.72°) (p < 0.001). Antibacterial activity testing displayed a significant decrease in bacterial growth for CM compared to ST (p = 0.001) and TE (p = 0.002); however, ST and TE showed no significant differences (p = 0.950). To conclude, ST Automix demonstrated promising results across several key parameters, making it a potential candidate for long-lasting restorative applications. Future studies should explore its long-term clinical performance and investigate formulations that enhance its antibacterial properties. Moreover, the bond strength of these materials to dentin and the cytotoxicity should be evaluated.
Keywords: antibacterial activity; compression strength; direct restorative materials; polymer-based; porosity; wettability
When Metal Complexes Evolve, and a Minor Species is the Most Active: the Case of Bis(Phenanthroline)Copper in the Catalysis of Glutathione Oxidation and Hydroxyl Radical Generation
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