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The combination of chemotherapy and gene therapy holds great promise for the treatment and eradication of tumors. However, due to significant differences in physicochemical properties between chemotherapeutic agents and functional nucleic acid drugs, direct integration into a single nano-agent is hindered, impeding the design and construction of an effective co-delivery nano-platform for synergistic anti-tumor treatments. In this study, we have developed an mRNA-responsive two-in-one nano-drug for effective anti-tumor therapy by the direct self-assembly of 2'-fluoro-substituted antisense DNA against P-glycoprotein (2'F-DNA) and chemo drug paclitaxel (PTX). The 2'-fluoro modification of DNA could significantly increase the interaction between the therapeutic nucleic acid and the chemotherapeutic drug, promoting the successful formation of 2'F-DNA/PTX nanospheres (2'F-DNA/PTX NSs). Due to the one-step self-assembly process without additional carrier materials, the prepared 2'F-DNA/PTX NSs exhibited considerable loading efficiency and bioavailability of PTX. In the presence of endogenous P-glycoprotein mRNA, the 2'F-DNA/PTX NSs were disassembled. The released 2'F-DNA could down-regulate the expression of P-glycoprotein, which decreased the multidrug resistance of tumor cells and enhanced the chemotherapy effect caused by PTX. In this way, the 2'F-DNA/PTX NSs could synergistically induce the apoptosis of tumor cells and realize the combined anti-tumor therapy. This strategy might provide a new tool to explore functional intracellular co-delivery nano-systems with high bioavailability and exhibit potential promising in the applications of accurate diagnosis and treatment of tumors.
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Terapia Genética , Paclitaxel , RNA Mensageiro , RNA Mensageiro/administração & dosagem , Paclitaxel/administração & dosagem , Paclitaxel/farmacologia , Paclitaxel/química , Humanos , Animais , Terapia Genética/métodos , Linhagem Celular Tumoral , Camundongos Nus , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Camundongos Endogâmicos BALB C , DNA/administração & dosagem , Nanopartículas/química , FemininoRESUMO
The Python-based program, XMECP, is developed for realizing robust, efficient, and state-of-the-art minimum energy crossing point (MECP) optimization in multiscale complex systems. This article introduces the basic capabilities of the XMECP program by theoretically investigating the MECP mechanism of several example systems including (1) the photosensitization mechanism of benzophenone, (2) photoinduced proton-coupled electron transfer in the cytosine-guanine base pair in DNA, (3) the spin-flip process in oxygen activation catalyzed by an iron-containing 2-oxoglutarate-dependent oxygenase (Fe/2OGX), and (4) the photochemical pathway of flavoprotein adjusted by the intensity of an external electric field. MECPs related to multistate reaction and multistate reactivity in large-scale complex biochemical systems can be well-treated by workflows suggested by the XMECP program. The branching plane updating the MECP optimization algorithm is strongly recommended as it provides derivative coupling vector (DCV) with explicit calculation and can equivalently evaluate contributions from non-QM residues to DCV, which can be nonadiabatic coupling or spin-orbit coupling in different cases. In the discussed QM/MM examples, we also found that the influence on the QM region by DCV can occur through noncovalent interactions and decay with distance. In the example of DNA base pairs, the nonadiabatic coupling occurs across the π-π stacking structure formed in the double-helix system. In contrast to general intuition, in the example of Fe/2OGX, the central ferrous and oxygen part contribute little to the spin-orbit coupling; however, a nearby arginine residue, which is treated by molecular mechanics in the QM/MM method, contributes significantly via two hydrogen bonds formed with α-ketoglutarate (α-KG). This indicates that the arginine residue plays a significant role in oxygen activation, driving the initial triplet state toward the productive quintet state, which is more than the previous knowledge that the arginine residue can bind α-KG at the reaction site by hydrogen bonds.
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Although metal-organic polyhedra (MOPs) expansion has been studied to date, it is still a rare occurrence for their porous intermolecular assembly for iodine capture. The major limitation is the lack of programmable and controllable methods for effectively constructing and utilizing the exterior cavities. Herein, the goal of programmable porous intermolecular assembly is realized in the first family of aluminum oxo polyhedrons (AlOPs) using ligands with directional H-bonding donor/acceptor pairs and auxiliary alcohols as structural regulation sites. The approach has the advantage of avoiding the use of expensive edge-directed ditopic and face-directed tritopic ligands in the general synthesis strategy of MOPs. Combining theoretical calculations and experiments, the intrinsic relationship is revealed between alcohol ligands and the growth mechanism of AlOPs. The maximum I2 uptake based on the mass gain during sorption corresponds to 2.35 g g-1, representing the highest reported I2 sorption by an MOP. In addition, it can be easily regenerated and maintained the iodine sorption capacity, revealing its further potential application. This method of constructing stable and programmable porous materials will provide a new way to solve problems such as radionuclide capture.
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Zeolitic metal-organic frameworks (ZMOFs) have emerged as one of the most promsing catalysts for energy conversion, but they suffer from either weak bonding between metal-organic cubes (MOCs) that decrease their stability during catalysis processes or low activity due to inadequate active sites. In this work, through ligand-directing strategy, we successfully obtain an unprecedented bismuth-based ZMOF (Bi-ZMOF) featuring a ACO topological crystal structure with strong coordination bonding between the Bi-based cages. As a result, it enables efficient reduction of CO2 to formic acid (HCOOH) with Faradaic efficiency as high as 91 %. A combination of in situ surface-enhanced infrared absorption spectroscopy and density functional theory calculation reveals that the Bi-N coordination contributes to facilitating charge transfer from N to Bi atoms, which stabilize the intermediate to boost the reduction efficiency of CO2 to HCOOH. This finding highlights the importance of the coordination environment of metal active sites on electrocatalytic CO2 reduction. We believe that this work will offer a new clue to rationally design zeolitic MOFs for catalytic reaction.
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In personalized cancer immunotherapy, developing an effective neoantigen nanovaccine with high immunogenicity is a significant challenge. Traditional nanovaccine delivery systems often require nanocarriers, which can hinder the delivery of the neoantigen and cause significant toxicity. In this study, we present an innovative strategy of carrier-free nanovaccine achieved through direct self-assembly of 2'-fluorinated CpG (2'F-CpG) with melanoma neoantigen peptide (Obsl1). Molecular dynamics simulations demonstrated that the introduction of a fluorine atom into CpG increases the noncovalent interaction between 2'F-CpG and Obsl1, which enhanced the loading of Obsl1 on 2'F-CpG, resulting in the spontaneous formation of a hybrid 2'F-CpG/Obsl1 nanovaccine. This nanovaccine without extra nanocarriers showed ultrahigh Obsl1 loading up to 83.19 wt %, increasing the neoantigen peptide uptake by antigen-presenting cells (APCs). In C57BL/6 mice models, we demonstrated the long-term preventive and therapeutic effects of the prepared 2'F-CpG/Obsl1 nanovaccine against B16F10 melanoma. Immunocellular analysis revealed that the nanovaccine activated innate and adaptive immune responses to cancer cells. Hence, this study established a simple, safe, and effective preparation strategy for a carrier-free neoantigen nanovaccine, which could be adapted for the future design of personalized cancer vaccines in clinical settings.
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Melanoma , Camundongos , Animais , Camundongos Endogâmicos C57BL , Melanoma/terapia , Células Apresentadoras de Antígenos , Transporte Biológico , PeptídeosRESUMO
Quercetin 2,4-dioxygenase (QueD) with various transition metal ion co-factors shows great differences, but the internal reasons have not been illustrated in detail. In order to explore the effects of metal ion centers on the catalytic reactivity of QueD, we calculated and compared the minimum energy crossing point (MECP) of dioxygen from the relatively stable triplet state to the active singlet state under different conditions by using the DFT method. It was found that the metal ions play a more important role in the activation of dioxygen compared with the substrate and the protein environment. Simultaneously, the catalytic reactions of the bacterial QueDs containing six different transition metal ions were studied by the QM/MM approach, and we finally obtained the reactivity sequence of metal ions, Ni2+ > Co2+ > Zn2+ > Mn2+ > Fe2+ > Cu2+, which is basically consistent with the previous experimental results. Our calculation results indicate that metal ions act as Lewis acids in the reaction to stabilize the substrate anion and the subsequent superoxo and peroxo species in the reaction, and promote the proton coupled electron transfer (PCET) process. Furthermore, the coordination tendencies of transition metal ion centers also have important effects on the catalytic cycle. These findings have general implications on metalloenzymes, which can expand our understanding on how various metal ions play their key role in modulating catalytic reactivity.
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The photocatalytic hydrogenation of CO2 by Cu-deposited ZnO (Cu/ZnO) polar surfaces is investigated through density functional theory (DFT) calculations combined with experimental work. The DFT results demonstrate that, without Cu-loading, CO2 and H2 present weak physisorption on the clean ZnO polar surface, except that H2 undergoes strong chemisorption on the ZnO(0001Ì) surface. Cu deposition on the ZnO polar surface could remarkably enhance the CO2 chemisorption ability, due to the induced charge redistribution on the interface of the Cu/ZnO polar surface systems. Additionally, a Cu-nanoisland, which was simulated using a Cu(111) slab model, exhibited strong ability to chemically adsorb H2. Thus, H2 may act as an adsorption competitor to CO2 on the Cu/ZnO(0001Ì), while, in contrast, CO2 and H2 (syngas) may have more opportunity to simultaneously adsorb on Cu/ZnO(0001) to promote the CO2 hydrogenation. These facet-dependent properties lead us to assume that Cu/ZnO(0001) should be a favorable photocatalyst for CO2 hydrogenation. This assumption is further verified by our photocatalysis experiment based on a ZnO single crystal. According to the theoretical and experimental results, the optimal HCOO* reaction pathway for the photocatalytic hydrogenation of CO2 on Cu/ZnO(0001) is proposed. In this optimal HCOO* path, the hydrogenation of CO2* step and hydrogenation of HCOO* step could be promoted by the coupling of a photo-generated spillover proton and a photoelectron on the interface of Cu/ZnO(0001). This research demonstrates the feasibility of the photocatalytic reduction of CO2 on Cu/ZnO(0001), and will help to develop related high-efficiency catalysts.
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Metal molecular rings are a class of compounds with aesthetically pleasing symmetry and fundamentally useful properties. The reported work generally focuses on the ring center cavity, and there is little known about those on the ring waist. Herein, we report the discovery of porous aluminum molecular rings and their performance and contribution to the cyanosilylation reaction. We develop a facile ligand induced aggregation and solvent regulation strategy towards AlOC-58NC and AlOC-59NT with high purity, high yield (75% and 70%, respectively) and gram-level scale-up. These molecular rings exhibit a "two-tier" pore feature involving the general central cavity and newly observed equatorial semi-open cavities. AlOC-59NT with two types of one-dimensional channels showed good catalytic activity. The interaction of the aluminum molecular ring catalyst with the substrate has been crystallographically characterized and theoretically confirmed, showing a ring adaptability process that involves the capture and binding of the substrate. This work provides new ideas for the assembly of porous metal molecular rings and to understand the overall reaction pathway involving aldehydes and is expected to inspire the design of low-cost catalysts through structural modifications.
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BACKGROUND: Breast cancer is the most common malignant tumor that threatens women's health. Attention has been paid on the study of long- non-coding RNA (lncRNA) in breast cancer. However, the specific mechanism remains not clear. METHODS: In this study, we explored the role of lncRNA BC069792 in breast cancer. In vitro and in vivo functional experiments were carried out in cell culture and mouse models. High-throughput next-generation sequencing technology and real-time fluorescence quantitative PCR technology were used to evaluate differentially expressed genes and mRNA expression, Western blot and immunohistochemical staining were used to detect protein expression. RNA immunoprecipitation assay and dual-luciferase activity assay were used to evaluate the competing endogenous RNAs (ceRNA), and rescue and mutation experiments were used for verification. RESULTS: We found that lncRNA BC069792 was expressed at a low level in breast cancer tissues, and significantly decreased in breast cancer with high pathological grade, lymph node metastasis and high Ki-67 index groups. Moreover, BC069792 inhibited the proliferation, invasion and metastasis of breast cancer cells in vitro and in vivo. Mechanically, BC069792 acts as a molecular sponge to adsorb hsa-miR-658 and hsa-miR-4739, to up-regulate the protein expression of Potassium Voltage-Gated Channel Q4 (KCNQ4), inhibits the activities of JAK2 and p-AKT, and plays a role in inhibiting breast cancer growth. CONCLUSIONS: LncRNA BC069792 plays the role of tumor suppressor gene in breast cancer and is a new diagnostic index and therapeutic target in breast cancer.
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Canais de Potássio KCNQ , Neoplasias , RNA Longo não Codificante , Animais , Feminino , Camundongos , Western Blotting , Técnicas de Cultura de Células , Modelos Animais de Doenças , MicroRNAs , Neoplasias/genética , Neoplasias/patologia , RNA Longo não Codificante/genética , HumanosRESUMO
Hydrogen-bonded organic frameworks (HOFs) are a rising class of promising proton-conducting materials. However, they always suffer from the inherent contradiction between chemical stability and proton conduction. Herein, inspired by the self-assembly of lipid bilayer membranes, a series of aminomethylphosphonic acid-derived single-component HOFs are successfully developed with different substituents attached to the phosphonate oxygen group. They remain highly stable in strong acid or alkaline water solutions for one month owing to the presence of charge-assisted hydrogen bonds. Interestingly, in the absence of external proton carriers, the methyl-substituted phosphonate-based HOF exhibits a very high proton conductivity of up to 4.2 × 10-3 S cm-1 under 80 °C and 98% relative humidity. This value is not only comparable to that of HOFs consisting of mixed ligands but also is the highest reported in single-component HOFs. A combination of single-crystal structure analysis and density functional theory calculations reveals that the high conductivity is attributed to the strengthened H-bonding interactions between positively charged amines and negatively charged phosphonate groups in the channel of bio-inspired HOFs. This finding demonstrates that the well-defined molecular structure of proton conductors is of great importance in the precise understanding of the relationship between structure and property.
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To create an artificial structure to remarkably surpass the sensitivity, selectivity and speed of the olfaction system of animals is still a daunting challenge. Herein, we propose a core-sheath pillar (CSP) architecture with a perfect synergistic interface that effectively integrates the advantages of metal-organic frameworks and metal oxides to tackle the above-mentioned challenge. The sheath material, NH2-MIL-125, can concentrate target analyte, nitro-explosives, by 1012 times from its vapour. The perfect band-matched synergistic interface enables the TiO2 core to effectively harvest and utilize visible light. At room temperature and under visible light, CSP (TiO2, NH2-MIL-125) shows an unexpected self-promoting analyte-sensing behaviour. Its experimentally reached limit of detection (â¼0.8 ppq, hexogeon) is 103 times lower than the lowest one achieved by a sniffer dog or all sensing techniques without analyte pre-concentration. Moreover, the sensor exhibits excellent selectivity against commonly existing interferences, with a short response time of 0.14 min.
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Southernmost Tibet exhibits an anomalously twice the normal thickness of average continental crust. There is no available theory to explain and the driving mechanism remains uncertain. Here, we interpret a north-striking, 180 km-long deep seismic reflection profile traversing the southern Lhasa terrane (SLT) to the central Lhasa terrane (CLT). In addition to reflections showing subducting Indian crust, our results reveal lateral heterogeneity between the SLT and CLT, where north-dipping reflections beneath the CLT outline a tilted crystalline basement, while the non-reflective domain beneath the SLT represents homogeneous juvenile crust. Our integrated analysis leads to models calling upon episodic magmatism onto the southern margin of the basement to result in progressive construction of the SLT. We hypothesize that this crustal thickening via crustal-scale magma accretion contributed to surface uplift of the southern margin of the Tibetan plateau and leading to the development of the vast internal drainage system of Tibet.
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The combination of gene therapy and chemotherapy provides a We developed a simple and versatile approach to prepare a series of two-in-one nanodrugs through direct self-assembly of cyanine-labeled single-stranded DNA (Cys-DNA) and different types of drug molecules. Molecular dynamics simulation showed that the Cys introduced into the DNA could enhance the noncovalent interaction between Cys-DNA and drug molecules. More drug molecules were incorporated into Cys-DNA, tending to spontaneously form hybrid Cys-DNA/drug nanosphere. Such nanospheres serve as both carriers and cargoes, excluding the extra use of nontherapeutic excipients and showing ultrahigh drug loading capacity. Following this approach, an antisense oligonucleotides/doxorubicin nanodrug model was constructed, demonstrating the significant synergistic anti-tumor therapeutic effect. As a proof of the concept, our study establishes a simple and reproducible two-in-one nucleic acid-based drug formulation.
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Antibióticos Antineoplásicos/farmacologia , Carbocianinas/química , DNA/química , Doxorrubicina/farmacologia , Nanopartículas/química , Oligonucleotídeos Antissenso/farmacologia , Antibióticos Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Dinâmica Molecular , Oligonucleotídeos Antissenso/química , Tamanho da PartículaRESUMO
Autophagy and apoptosis are dynamic processes that determine the fate of cells, and regulating these processes can treat cancer. GEFT is highly expressed in rhabdomyosarcoma (RMS), which accelerates the tumorigenicity and metastasis of RMS by activating Rac1/Cdc42 signaling, but the regulatory mechanisms of autophagy and apoptosis are unclear. In our study, we found that the RMS tissues had high Rac1, Cdc42, mTOR, and Bcl-2 expression levels and low Beclin1, LC3, and Bax expression levels compared with the normal striated muscle tissues (P < 0.05). In addition, multivariate analysis has proven that Rac1 is an independent prognostic factor (P < 0.05), and the high expression level of the Beclin1 protein was closely associated with the tumor diameter of the RMS patients (P = 0.044), whereas the high expression level of the LC3 protein was associated with the clinical stage of the RMS patients (P = 0.027). Furthermore, GEFT overexpression could inhibit autophagy and apoptosis in RMS. A Rac1/Cdc42 inhibitor was added, and the inhibition of autophagy and apoptosis decreased. Rac1 and Cdc42 could regulate mTOR to inhibit autophagy and apoptosis in RMS. Overall, these studies demonstrated that the GEFT-Rac1/Cdc42-mTOR pathway can inhibit autophagy and apoptosis in RMS and provide evidence for innovative treatments.
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The rational design based on a deep understanding of the present reaction mechanism is an important, viable approach to discover new organic transformations. ß-Hydrogen elimination from palladium complexes is a fundamental reaction in palladium catalysis. Normally, the eliminated ß-hydrogen has to be attached to a sp3-carbon. We envision that the hydrogen elimination from sp2-carbon is possible by using thoroughly designed reaction systems, which may offer a new strategy for the preparation of allenes. Here, we describe a palladium-catalyzed cross-coupling of 2,2-diarylvinyl bromides and diazo compounds, where a ß-vinylic hydrogen elimination from allylic palladium intermediate is proposed to be the key step. Both aryl diazo carbonyl compounds and N-tosylhydrazones are competent carbene precursors in this reaction. The reaction mechanism is explored by control experiments, KIE studies and DFT calculations.
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Isolated intracranial myeloid sarcoma (MS) is an unusual variant tumor with few cases reported so far in the medical literature. A 29-year-old woman was admitted to our hospital presenting progressive visual loss in the right eye and weight loss (20 kg) without a previous history of hematological disease (HD). Radiologic evaluation showed the evidence of intracranial mass. Histologically, the resected tumor was composed of a uniform population of primitive cells and primarily misdiagnosed as a T-cell non-Hodgkin's lymphoma (NHL). Chemotherapy with cyclophosphamide, doxorubicin, vinblastine, and prednisone (CHOP) was ineffective. A biopsy and histopathological evaluation were repeated, and immunohistochemical staining revealed the positivity of immature cells to an extensive panel of myeloid markers. These findings were consistent with a diagnosis of MS and bone marrow infiltration. Literature reviews of previous cases were also undertaken.
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Nanobactericides represent one of the most efficient and promising strategies for eliminating bacterial infection considering the increasing resistance threats of conventional antibiotics. Black phosphorus (BP) is the most exciting postgraphene layered 2D nanomaterial with convincing physiochemical properties, yet the study of BP-based antibiotics is still in its infancy. Here, a compact silver nanoparticle (AgNP)-doped black phosphorus nanosheet (BPN) is constructed to synergistically enhance solar disinfection through the promoted reactive oxygen species (ROS) photogeneration, which is attributed to the improved electron-hole separation and recombination of BPNs as revealed from the systematic experimental studies. An in-depth density functional theory (DFT) calculation confirms that the integrated AgNPs provide a preferred site for facilitating the adsorption and activation of O2 , thus promoting the more efficient and robust ROS generation on BPN-AgNP nanohybrids. Besides the enhanced photoinduced ROS, the anchored AgNPs simultaneously lead to a dramatically increased affinity toward bacteria, which facilitates a synergetic pathogen inactivation. Significantly, the convincing antimicrobial BPN-AgNP contributes to the prominent wound healing and antimicrobial ability in vivo with minimized biological burden. This sophisticated design of new 2D nanohybrids opens a new avenue for further exploiting BP-based nanohybrids in portable bandage and broad-spectrum disinfection applications.
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Infecções Bacterianas , Nanoestruturas , Fósforo , Prata , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Fósforo/uso terapêutico , Ratos , Prata/uso terapêutico , Pele/lesões , Pele/microbiologia , Cicatrização/efeitos dos fármacosRESUMO
Reactions that efficiently construct medium-sized lactones are significant, as they overcome the unfavorable entropic factor and transannular interactions for ring closure, and the lactones produced are common structural motifs recurring in many biologically active compounds. Herein, we describe a valuable strategy for medium-sized lactone synthesis by accomplishing site-selective C-H bond functionalization via a palladium carbene migratory insertion enabled 1,4-palladium shift. The overall process achieves the formal dimerization of two readily available benzaldehyde derivatives, providing value-added products medium-sized lactones. Our method is amenable to late-stage modification of approved drugs and other complex molecules. Mechanistic studies including deuterium-labeling experiments and DFT calculation shed light on the reaction pathways.
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Atomically thin colloidal quasi-two-dimensional (2D) semiconductor nanoplatelets (NPLs) have attracted tremendous attention due to their excellent properties and stimulating applications. Although some advances have been achieved in Cd- and Pb-based semiconductor NPLs, research into heavy-metal-free NPLs has been reported less due to the difficulties in the synthesis and the knowledge gap in the understanding of the growth mechanism. Herein wurtzite ZnTe NPLs with an atomic thickness of about 1.5 nm have been successfully synthesized by using Superhydride (LiEt3BH) reduced tributylphosphine-Te (TBP-Te) as the tellurium precursor. Mechanistic studies, both experimentally and theoretically, elucidate the transformation from metastable ZnTe MSC-323 magic-size nanoclusters (MSCs) to metastable ZnTe MSC-398, which then forms wurtzite ZnTe NPLs via an oriented attachment mechanism along the [100] and [002] directions of the wurtzite structure. This work not only provides insightful views into the growth mechanism of 2D NPLs but also opens an avenue for their applications in optoelectronics.
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Multiscale simulations have been performed to address the longstanding issue of "dioxygen activation" by the binuclear copper monooxygenases (PHM and DßM), which have been traditionally classified as "noncoupled" binuclear copper enzymes. Our QM/MM calculations rule out that CuM(II)-O2⢠is an active species for H-abstraction from the substrate. In contrast, CuM(II)-O2⢠would abstract an H atom from the cosubstrate ascorbate to form a CuM(II)-OOH intermediate in PHM and DßM. Consistent with the recently reported structural features of DßM, the umbrella sampling shows that the "open" conformation of the CuM(II)-OOH intermediate could readily transform into the "closed" conformation in PHM, in which we located a mixed-valent µ-hydroperoxodicopper(I,II) intermediate, (µ-OOH)Cu(I)Cu(II). The subsequent O-O cleavage and OH moiety migration to CuH generate the unexpected species (µ-Oâ¢)(µ-OH)Cu(II)Cu(II), which is revealed to be the reactive intermediate responsible for substrate hydroxylation. We also demonstrate that the flexible Met ligand is favorable for O-O cleavage reactions, while the replacement of Met with the strongly bound His ligand would inhibit the O-O cleavage reactivity. As such, the study not only demonstrates a "coupled" mechanism for O2 activation by binuclear copper monooxygenases but also deciphers the full catalytic cycle of PHM and DßM in accord with the available experimental data. These findings of O2 activation and substrate hydroxylation by binuclear copper monooxygenases could expand our understanding of the reactivities of the synthetic monocopper complexes.