One-Pot Synthesis of a Mixed-Valent Copper(I/II)-Coordinated Covalent Organic Framework Induced by γ-Ray Radiation.

Metal-anchored covalent organic frameworks (COFs), as a class of significant derivatives of COFs, are widely used as heterogeneous catalysts in diverse chemical reactions. However, they are typically synthesized via post-treatment strategies, which often lead to the decline of COF crystallinity, decrease of porous properties, instability in catalytic performances, generation of additional chemical waste, and consumption of excess time and energy. In this work, we demonstrate an approach to construct a metal-functionalized COF via a one-pot method induced by γ-ray radiation. Specifically, copper-coordinated COF was in situ synthesized by irradiating a mixture of monomers and copper salt under ambient conditions. Interestingly, the initial Cu2+ ions were reduced to Cu+ ions by the radiation-generated reducing species, affording a unique mixed-valent copper(I/II)-coordinated COF. Additionally, the copper-coordinated COF displayed enhanced crystallinity and porous properties compared to those of the parent COF, displaying an opposite trend to the postsynthetic method. Notably, the introduced copper on the COF skeleton endowed the parent COF with catalytic ability. The resulting copper-coordinated COF exhibited remarkable catalytic performances in the reduction of 4-nitrophenol to 4-aminophenol and maintained almost unchanged catalytic performance after five catalytic cycles.

A MOF@Metal Oxide Heterostructure Induced by Post-Synthetic Gamma-Ray Irradiation for Catalytic Reduction.

Metal-organic framework (MOF) based heterostructures, which exhibit enhanced or unexpected functionality and properties due to synergistic effects, are typically synthesized using post-synthetic strategies. However, several reported post-synthetic strategies remain unsatisfactory, considering issues such as damage to the crystallinity of MOFs, presence of impure phases, and high time and energy consumption. In this work, we demonstrate for the first time a novel route for constructing MOF based heterostructures using radiation-induced post-synthesis, highlighting the merits of convenience, ambient conditions, large-scale production, and notable time and energy saving. Specifically, a new HKUST-1@Cu2O heterostructure was successfully synthesized by simply irradiating a methanol solution dispersed of HKUST-1 with gamma ray under ambient conditions. The copper source of Cu2O was directly derived from in situ radiation etching and reduction of the parent HKUST-1, without the use of any additional copper reagents. Significantly, the resulting HKUST-1@Cu2O heterostructure exhibits remarkable catalytic performance, with a catalytic rate constant nearly two orders of magnitude higher than that of the parent HKUST-1.

Radiation-Assisted Assembly of a Highly Dispersed Nanomolybdenum-Functionalized Covalent Organic Framework.

Two-dimensional covalent organic frameworks (2D COFs), featuring a large surface area and 1D pore structure, serve as promising scaffolds for anchoring functional guest compounds, which can significantly enhance their performance and thus expand their potential applications. Postsynthetic strategy for COFs functionalization is versatile but challenging because of their tedious procedure with high time and energy consumption, generation of excess reaction waste, and damage to COF crystallinity. We report in this work a general strategy for the synthesis of inorganic nanocompound-functionalized COF composites in a one-pot way. Specifically, a high-crystallinity nanoscale molybdenum compound is successfully introduced into a COF skeleton with high dispersion in situ during the crystallization process of the COF induced by gamma ray radiation under ambient conditions. The obtained COF@Mo composites exhibit remarkable sorption performance for methylene blue and many other organic dyes in aqueous solution with the advantages of ultrarapid uptake dynamics and high removal efficiency.

Highly efficient catalytic Fenton-Like reactions of bimetallic Fe/Cu chelated on radiation functionalized nonwoven fabric for pollutant control.

A remarkably efficient and affordable Fe/Cu bimetallic catalyst featuring a substantial light energy utilization and compatibility with a sizable substrate was developed for Fenton-like reactions aimed at pollutant control. Specifically, a novel strategy was employed to synthesize high-density metal sites (Fe:Cu ≈ 3:1) robustly embedded on polyethylene/polyethylene terephthalate nonwoven fabric (PE/PET NWF) via radiation-induced graft polymerization (RIGP) and subsequent chemical modification, labeled as Fe/Cu-PPAO. Its high effectiveness was demonstrated by degrading 50 mg/L of tetracycline hydrochloride within 30 min in the presence of H2O2 under simulate sunlight irradiation. It was investigated that amidoxime groups regulated the optical gaps and HOMO-LUMO gaps of metal ions to enable the absorption of a broader spectrum light while the Cu2+ facilitated the transfer of electrons between the bimetal ions to achieve an improved reaction path. Furthermore, X-ray absorption fine structure (XAFS) and density functional theory (DFT) calculations further revealed its special complex state and delicate electronic structure between bimetal ions and amidoxime groups. Our study offers a new strategy to synthesize high-density bimetallic sites catalyst for environmental remediation and pushes forward insight into understanding the catalytic mechanism of bimetallic Fenton-like catalysts.

Anti-osteoarthritis, Bone Protective and Antiinflammatory Effect of Lusianthridin against Monosodium Iodoacetate Induced Osteoarthritis via Suppression of Inflammatory Pathway.

Osteoarthritis (OA) is characterized by the gradual deterioration and worsening of the knee joint, leading to both pain and deformity. The current research exhibited the anti-osteoarthritis effect of lusianthridin against monosodium iodoacetate (MIA) induced OA in rats. RAW cells were used for the cell viability. The inflammatory cytokines and mediators were estimated in the cell lines after the lipopolysaccharide (LPS) treatment. For the in vivo study, the rats were received the intraperitoneal administration of MIA (3 mg/kg) for the induction of OA. The rats were received the oral administration of lusianthridin (5, 10 and 20 mg/kg) and the body and organ weight estimated. Antioxidant, cytokines, inflammatory and matrix metalloproteinases (MMP) level were also estimated. The mRNA expression of MMP were also estimated. The lusianthridin treatment remarkably suppressed the cell viability. LPS induced RAW cell suppressed the level of nitrate, tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), cyclooxygenase-2 (COX-2), prostaglandin (PGE2), MMP-2 and MMP-9 level. Lusianthridin remarkably altered the level of body weight and organ weight (liver, spleen, renal and heart weight). lusianthridin suppressed the oxidative stress via altered the level of antioxidant parameters. Lusianthridin significantly (p < 0.001) decreased the level of cartilage oligometrix matrix protein (COMP) and c-reactive protein (CRP); cytokines such as TNF-α, IL-1ß, IL-6, IL-10; inflammatory parameters include 5- Lipoxygenase (5-LOX), COX-2, leukotriene B4 (LTB4), PGE2; transforming growth factor beta (TGF-ß); MMP level like MMP-1, 3, 9, 13, respectively. Lusianthridin significantly suppressed the mRNA expression of MMP. Collectively, the result of the study showed that antiosteoarthritis effect of lusianthridin via suppression of inflammatory parameters.