Search Results (4)

The strategic design of donor–acceptor (D-A) conjugated porous polymers has emerged as a pivotal methodology for advancing efficient photocatalytic hydrogen evolution. However, conventional D-A polymeric architectures face inherent limitations: excessively strong acceptor units may lower the LUMO energy level, compromising proton (H⁺) reduction capability, while weak D-A interactions result in inadequate light-harvesting capacity and insufficient photogenerated electrons, ultimately diminishing photocatalytic activity. To address these challenges, we developed a new D1-A-D2 conjugated porous polymer (CPP) system. The strategic incorporation of a secondary donor benzothiophene (DBBTh) unit enabled precise bandgap engineering in D₁-A-D₂ CPPs. Experimental results demonstrate that DBBTh integration significantly enhances both light absorption efficiency and proton reduction ability. Under visible-light irradiation (λ > 420 nm), the Py-BKh1 photocatalyst achieved a hydrogen evolution rate (HER) of 10.2 mmol h⁻¹ g⁻¹ with an apparent quantum yield (AQY) of 9.5% at 500 nm. This work provides a groundbreaking paradigm for designing high-performance organic photocatalysts. Full article

Here, we synthesized and characterized a novel two-dimensional (2D) conjugated electron donor–acceptor (D-A) copolymer (PBDB-T-Ge), wherein the substituent of triethyl germanium was added to the electron donor unit of the polymer. The Turbo–Grignard reaction was used to implement the group IV element into the polymer, resulting in a yield of 86%. This corresponding polymer, PBDB-T-Ge, exhibited a down-shift in the highest occupied molecular orbital (HOMO) level to −5.45 eV while the lowest unoccupied molecular orbital (LUMO) level was −3.64 eV. The peaks in UV-Vis absorption and the PL emission of PBDB-T-Ge were observed at 484 nm and 615 nm, respectively. Full article

The development of conjugated polymer-based nanocomposites by adding metallic particles into the polymerization medium allows the proposition of novel materials presenting improved electrical and optical properties. Polyaniline Emeraldine-salt form (ES–PANI) has been extensively studied due to its controllable electrical conductivity and oxidation states. On the other hand, tungsten oxide (WO₃) and its di-hydrated phases, such as WO₃·2H₂O, have been reported as important materials in photocatalysis and sensors. Herein, the WO₃·2H₂O phase was directly obtained during the in-situ polymerization of aniline hydrochloride from metallic tungsten (W), allowing the formation of hybrid nanocomposites based on its full oxidation into WO₃·2H₂O. The developed ES–PANI–WO₃·2H₂O nanocomposites were successfully characterized using experimental techniques combined with Density Functional Theory (DFT). The formation of WO₃·2H₂O was clearly verified after two hours of synthesis (PW₂ nanocomposite), allowing the confirmation of purely physical interaction between matrix and reinforcement. As a result, increased electrical conductivity was verified in the PW₂ nanocomposite: the DFT calculations revealed a charge transfer from the p-orbitals of the polymeric phase to the d-orbitals of the oxide phase, resulting in higher conductivity when compared to the pure ES–PANI. Full article

Non-viral transfection reagents are continuously being developed in attempt to replace viral vectors. Among those non-viral vectors, dendrimers have gained increasing interest due to their unique molecular structure and multivalency. However, more improvements are still needed to achieve higher efficacy and lower toxicity. In this study, we have examined 18 peptide dendrimers conjugated to lipophilic moieties, such as fatty acids or hydrophobic amino acids, that were previously explored for siRNA. Reporter cells were employed to investigate the transfection of single strand splice-switching oligonucleotides (ONs) using these peptide dendrimers. Luciferase level changes reflecting efficiency varied with amino acid composition, stereochemistry, and complexation media used. 3rd generation peptide dendrimers with D-amino acid configuration were superior to L-form. Lead formulations with 3rd generation, D-amino acid peptide dendrimers increased the correction level of the delivered ON up to 93-fold over untreated HeLa Luc/705 cells with minimal toxicity. To stabilize the formed complexes, Polyvinyl alcohol 18 (PVA18) polymer was added. Although PVA18 addition increased activity, toxicity when using our best candidates G 2,3KL-(Leu)₄ (D) and G 2,3KL-diPalmitamide (D) was observed. Our findings demonstrate the potential of lipid-conjugated, D-amino acid-containing peptide dendrimers to be utilized as an effective and safe delivery vector for splice-switching ONs. Full article