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The unique thermodynamic and kinetic coordination chemistry of ruthenium allows it to modulate key adverse aggregation and membrane interactions of α-synuclein (α-syn) associated with Parkinson's disease. We show that the low-toxic Ru

The single-atom enzyme (SAE) is a novel type of nanozyme that exhibits extraordinary catalytic activity. Here, we constructed a PEGylated manganese-based SAE (Mn/PSAE) by coordination of single-atom manganese to nitrogen atoms in hollow zeolitic imidazolate frameworks. Mn/PSAE catalyzes the conversion of cellular H2 O2 to . OH through a Fenton-like reaction; it also promotes the decomposition of H2 O2 to O2 and continuously catalyzes the conversion of O2 to cytotoxic . O2 - via oxidase-like activity. The catalytic activity of Mn/PSAE is more pronounced in the weak acidic tumor environment; therefore, these cascade reactions enable the sufficient generation of reactive oxygen species (ROS) and effectively kill tumor cells. The prominent photothermal conversion property of the amorphous carbon can be utilized for photothermal therapy. Hence, Mn/PSAE exhibits significant therapeutic efficacy through tumor microenvironment stimulated generation of multiple ROS and photothermal activity.

Efficient electrocatalytic reactions require a coordinated active center that may provide a properly reaction intermediates adsorption in water splitting. Herein, a Ni active center coordination reconstruction method achieved by multidimensional modulation of phase transition, iodine coordination, and vacancy defects is designed and implemented. This coordination reconstruction results in the successful synthesis of Ni

The targeted delivery of chemotherapeutic drugs is a major challenge in the clinical treatment of cancer. Herein, we constructed a multifunctional DNA nanoplatform as a versatile carrier of the highly potent platinum-based DNA intercalator, 56MESS. In our rational design, 56MESS was efficiently loaded into the double-bundle DNA tetrahedron through intercalation with the DNA duplex. With the integration of a nanobody that both targets and blocks epidermal growth factor receptor (EGFR), the DNA nanocarriers exhibit excellent selectivity for cells with elevated EGFR expression (a common biomarker related to tumor formation) and combined tumor therapy without obvious systemic toxicity. This DNA-based platinum-drug delivery system provides a promising strategy for the treatment of tumors.

Hypoxia is a hallmark of the tumor microenvironment (TME) that promotes tumor development and metastasis. Photodynamic therapy (PDT) is a promising strategy in the treatment of tumors, but it is limited by the lack of oxygen in TME. In this work, an O

In this study, diacylglycerols (DAG) were synthesized rapidly (~30 min) in a solvent-free system via esterification of glycerol with fatty acids (FA, the mixture of 60 wt% palm oil deodorizer distillate and 40 wt% oleic acid) catalyzed by Lipozyme 435 (Novozymes A/S, Copenhagen, Denmark) using a bubble column reactor. The content of DAG, monoacylglycerols (MAG), triacylglycerols (TAG) and free fatty acids (FFA) in the crude product were 57.94 ± 1.60 wt%, 24.68 ± 2.08 wt%, 2.67 ± 1.72 wt% and 14.69 ± 1.22 wt%, respectively under the selected conditions, which were enzyme load of 5.0 wt%, glycerol/FA mole ratio of 7.5, initial water content of 2.5 wt%, reaction temperature of 60 °C, reaction time of 30 min and N2 gas flow of 10.6 cm min−1. The final product containing 91.30 ± 1.10 wt% of DAG was obtained by one-step molecular distillation at 200 °C. The reusability of Lipozyme 435 was investigated by evaluating the esterification degree (ED) and the DAG content in the crude products in 30 successive runs. The enzyme retained 95.10 % of its original activity during 30 successive runs according to comparison of the ED. The new process showed a very high efficiency in production of DAG with a high purity. The ratio of positional isomers 1,3-DAG to 1,2 -DAG was 2:1 in the final product. The certain plasticity (melting point of 44 °C) and content of unsaturated fatty acids made the product a valuable food ingredient.

Lead halide perovskites (LHPs) have received increased attention owing to their intriguing optoelectronic and photonic properties. However, the toxicity of lead and the lack of long-term stability are potential obstacles for the application of LHPs. Herein, the epitaxial synthesis of CsPbX3 (X = Cl, Br, I) perovskite quantum dots (QDs) by surface chemical conversion of Cs2 GeF6 double perovskites with PbX2 (X = Cl, Br, I) is reported. The experimental results show that the surface of the Cs2 GeF6 double perovskites is partially converted into CsPbX3 perovskite QDs and forms a CsPbX3 /Cs2 GeF6 hybrid structure. The theoretical calculations reveal that the CsPbBr3 conversion proceeds at the Cs2 GeF6 edge through sequential growth of multiple PbBr6 4- layers. Through the conversion strategy, luminescent and color-tunable CsPbX3 QDs can be obtained, and these products present high stability against decomposition due to anchoring effects. Moreover, by partially converting red emissive Cs2 GeF6 :Mn4+ to green emissive CsPbBr3 , the CsPbBr3 /Cs2 GeF6 :Mn4+ hybrid can be employed as a low-lead hybrid perovskite phosphor on blue LED chips to produce white light. The leadless CsPbX3 /Cs2 GeF6 hybrid structure with stable photoluminescence opens new paths for the rational design of efficient emission phosphors and may stimulate the design of other functional CsPbX3 /Cs-containing hybrid structures.

Niobium aluminum carbide (Nb4AlC3), as a member of the MAX phases, can retain its stiffness and strength up to over 1400°C, however, the strength at room temperature is relatively low. In this work, Nb5(Si, Al)3 was used to strengthen Nb4AlC3. Nb4AlC3–Nb5(Si, Al)3 composites with different amount of Nb5(Si, Al)3 were synthesized from the elemental powders by in situ hot-pressing/solid–liquid reaction synthesis process. The RT flexural strength was significantly improved from 370 MPa of monolithic Nb4AlC3 to 432 MPa of Nb4AlC3-15 vol% Nb5(Si, Al)3 composite without the degradation of its high-temperature mechanical properties. While a slightly decrease in fracture toughness occurs with the increment of Nb5(Si, Al)3 content. Meanwhile, Transmission electron microscopy (TEM) observations reveal that the interfaces between Nb4AlC3/Nb4AlC3, Nb4AlC3/Nb5(Si, Al)3, and Nb5(Si, Al)3/Nb5(Si, Al)3 are free of amorphous layers, which is also beneficial to its high-temperature mechanical properties.

The oxidation reaction between cerium(IV) and Tween 85 in sulfuric acid medium produced weak chemiluminescence (CL). In this paper, it was found that citrate could strongly enhance the CL of cerium(IV)-Tween 85-polyphenol system. Based on studies of ultraviolet-visible spectra and CL spectra, the CL enhancement mechanism had been proposed. It was surmised that the light emission was from an excited oxygen molecular pair O2((1)Δg)O2((1)∑g(-)). The maximum emission wavelength was about 478 nm. The effects of 17 amino acids and 29 organic compounds on cerium(IV)-Tween 85-citrate CL were investigated by a flow injection procedure. This study showed the present system had a wide application for the determination of these compounds.