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Chemical Communications (Cambridge,... Jul 2024Direct photocatalytic C-H activation mediated by MoOCl(bpy-Bu), a unique photoactive metal OXO, is presented. The limiting step, reoxidation to the Mo dioxo, is...
Direct photocatalytic C-H activation mediated by MoOCl(bpy-Bu), a unique photoactive metal OXO, is presented. The limiting step, reoxidation to the Mo dioxo, is evaluated and proposed to occur a key Cl loss event. Photocatalyst degradation occurs upon substitution of bpy-Bu with HO generated during catalysis.
PubMed: 38888147
DOI: 10.1039/d4cc01789g -
Small (Weinheim An Der Bergstrasse,... Jun 2024Tumor-associated macrophages (TAMs) play a crucial function in solid tumor antigen clearance and immune suppression. Notably, 2D transitional metal dichalcogenides...
Tumor-associated macrophages (TAMs) play a crucial function in solid tumor antigen clearance and immune suppression. Notably, 2D transitional metal dichalcogenides (i.e., molybdenum disulfide (MoS) nanozymes) with enzyme-like activity are demonstrated in animal models for cancer immunotherapy. However, in situ engineering of TAMs polarization through sufficient accumulation of free radical reactive oxygen species for immunotherapy in clinical samples remains a significant challenge. In this study, defect-rich metastable MoS nanozymes, i.e., 1T2H-MoS, are designed via reduction and phase transformation in molten sodium as a guided treatment for human breast cancer. The as-prepared 1T2H-MoS exhibited enhanced peroxidase-like activity (≈12-fold enhancement) than that of commercial MoS, which is attributed to the charge redistribution and electronic state induced by the abundance of S vacancies. The 1T2H-MoS nanozyme can function as an extracellular hydroxyl radical generator, efficiently repolarizing TAMs into the M1-like phenotype and directly killing cancer cells. Moreover, the clinical feasibility of 1T2H-MoS is demonstrated via ex vivo therapeutic responses in human breast cancer samples. The apoptosis rate of cancer cells is 3.4 times greater than that of cells treated with chemotherapeutic drugs (i.e., doxorubicin).
PubMed: 38888117
DOI: 10.1002/smll.202402101 -
Nanoscale Jun 2024The rise of two-dimensional (2D) materials has provided a confined geometry and yielded methods for guiding electrons at the nanoscale level. 2D material-enabled...
The rise of two-dimensional (2D) materials has provided a confined geometry and yielded methods for guiding electrons at the nanoscale level. 2D material-enabled electronic devices can interact and transduce the subtle charge perturbation and permit significant advancement in molecule discrimination technology with high accuracy, sensitivity, and specificity, leaving a significant impact on disease diagnosis and health monitoring. However, high-performance biosensors with scalable fabrication ability and simple protocols have yet to be fully realized due to the challenges in wafer-scale 2D film synthesis and integration with electronics. Here, we propose a molybdenum oxide (MoO)-interdigitated electrode (IDE)-based label-free biosensing chip, which stands out for its wafer-scale dimension, tunability, ease of integration and compatibility with the complementary metal-oxide-semiconductor (CMOS) fabrication. The device surface is biofunctionalized with monoclonal anti-carcinoembryonic antigen antibodies (anti-CEA) the linkage agent (3-aminopropyl)triethoxysilane (APTES) for carcinoembryonic antigen (CEA) detection and is characterized step-by-step to reveal the working mechanism. A wide range and real-time response of the CEA concentration from 0.1 to 100 ng mL and a low limit of detection (LOD) of 0.015 ng mL were achieved, meeting the clinical requirements for cancer diagnosis and prognosis in serum. The MoO-IDE biosensor also demonstrates strong surface affinity towards molecules and high selectivity using L-cysteine (L-Cys), glycine (Gly), glucose (Glu), bovine serum albumin (BSA), and immunoglobulin G (IgG). This study showcases a simple, scalable, and low-cost strategy to create a nanoelectronic biosensing platform to achieve high-performance cancer biomarker discrimination capabilities.
PubMed: 38887082
DOI: 10.1039/d4nr01275e -
Journal of Nanobiotechnology Jun 2024Molybdenum disulfide (MoS) has excellent physical and chemical properties. Further, chiral MoS (CMS) exhibits excellent chiroptical and enantioselective effects, and the...
BACKGROUND
Molybdenum disulfide (MoS) has excellent physical and chemical properties. Further, chiral MoS (CMS) exhibits excellent chiroptical and enantioselective effects, and the enantioselective properties of CMS have been studied for the treatment of neurodegenerative diseases. Intriguingly, left- and right-handed materials have different effects on promoting the differentiation of neural stem cells into neurons. However, the effect of the enantioselectivity of chiral materials on peripheral nerve regeneration remains unclear.
METHODS
In this study, CMS@bacterial cellulose (BC) scaffolds were fabricated using a hydrothermal approach. The CMS@BC films synthesized with L-2-amino-3-phenyl-1-propanol was defined as L-CMS. The CMS@BC films synthesized with D-2-amino-3-phenyl-1-propanol was defined as D-CMS. The biocompatibility of CMS@BC scaffolds and their effect on Schwann cells (SCs) were validated by cellular experiments. In addition, these scaffolds were implanted in rat sciatic nerve defect sites for three months.
RESULTS
These chiral scaffolds displayed high hydrophilicity, good mechanical properties, and low cytotoxicity. Further, we found that the L-CMS scaffolds were superior to the D-CMS scaffolds in promoting SCs proliferation. After three months, the scaffolds showed good biocompatibility in vivo, and the nerve conducting velocities of the L-CMS and D-CMS scaffolds were 51.2 m/s and 26.8 m/s, respectively. The L-CMS scaffolds showed a better regenerative effect than the D-CMS scaffolds. Similarly, the sciatic nerve function index and effects on the motor and electrophysiological functions were higher for the L-CMS scaffolds than the D-CMS scaffolds. Finally, the axon diameter and myelin sheath thickness of the regenerated nerves were improved in the L-CMS group.
CONCLUSION
We found that the CMS@BC can promote peripheral nerve regeneration, and in general, the L-CMS group exhibited superior repair performance. Overall, the findings of this study reveal that CMS@BC can be used as a chiral nanomaterial nerve scaffold for peripheral nerve repair.
Topics: Nerve Regeneration; Animals; Rats; Tissue Scaffolds; Disulfides; Schwann Cells; Molybdenum; Cellulose; Rats, Sprague-Dawley; Biocompatible Materials; Sciatic Nerve; Cell Proliferation; Tissue Engineering; Male; Peripheral Nerve Injuries; Stereoisomerism
PubMed: 38886712
DOI: 10.1186/s12951-024-02493-6 -
Dalton Transactions (Cambridge, England... Jul 2024This study employs plasma-liquid interaction technique to synthesize different phases of molybdenum oxide using air and argon as plasma-forming gases. plasma-generated...
This study employs plasma-liquid interaction technique to synthesize different phases of molybdenum oxide using air and argon as plasma-forming gases. plasma-generated nitrogen species primarily NO/NO and hydrogen species (H) facilitate the reduction of the molybdenum precursor anion (MoO). The reduced Mo species subsequently reacts with reactive oxygen species, forming MoO octahedra, which is the building block of a molybdenum oxide crystal. Varied concentrations of NO/NO and H species in air and argon plasma treatment significantly influence the growth process. Air plasma synthesis yields hexagonal molybdenum oxide microrods, which upon calcination changes its phase to orthorhombic 2D layered structure. Moreover, the argon plasma synthesized sample exhibits a mixed phase of hexagonal and orthorhombic molybdenum oxide due to the heavy argon ion bombardment, inducing material porosity and surface oxygen vacancies. The mixed-phase material exhibits superior adsorption and photo-degradation towards cationic dye compared to the other two phases. The higher photocatalytic performance may be responsible for the extended lifetime of the photo-generated charge carriers possessed by the mixed-phase material. Radical scavenging tests have identified holes and hydroxyl radicals as the key reactive species that take part in the photo-degradation process.
PubMed: 38885122
DOI: 10.1039/d4dt01620c -
Science and Technology of Advanced... 2024The hydrogen evolution reaction (HER) is an important phenomenon in water splitting. Consequently, the development of an active, earth-abundant, and inexpensive HER...
The hydrogen evolution reaction (HER) is an important phenomenon in water splitting. Consequently, the development of an active, earth-abundant, and inexpensive HER catalyst is highly desired. MoS has drawn considerable interest as an HER catalyst because it is composed of non-precious metal and exhibits high catalytic activity in the nanosheet form. In this study, size-controlled MoS particles were synthesized by ball milling. The as-prepared samples exhibited significantly enhanced electrochemical and catalytic properties compared to those of pristine bulk MoS. Furthermore, the HER activity improved further upon the introduction of graphene into the as-prepared ball-milled samples. In particular, the MoS sample ball-milled for 12 h mixed with graphene exhibited optimal performance, showing an overpotential (160 mV at 10 mA cm) that was ~ 335 mV lower than that of pristine bulk MoS. The superior catalytic activity was ascribed to the exposed edge sites, sulfur vacancies, and 1T phase of MoS, as well as the noteworthy fortifying effect of the electronically conductive flexible material, graphene. The results provide a promising strategy for its application as an efficient and stable HER catalyst.
PubMed: 38882258
DOI: 10.1080/14686996.2024.2359360 -
ACS Omega Jun 2024Transition-metal dichalcogenides (TMDs) and their alloys are vital for the development of sustainable and economical energy storage alternatives due to their large...
Transition-metal dichalcogenides (TMDs) and their alloys are vital for the development of sustainable and economical energy storage alternatives due to their large interlayer spacing and hosting ability for alkali-metal ions. Although the Li-ion chemically correlates with the Na-ion and K-ion, research on batteries with TMD anodes for K is still in its infancy. This research explores TMDs such as molybdenum disulfide (MoS) and tungsten disulfide (WS) and TMD alloys such as molybdenum tungsten disulfide (MoWS) for both sodium-ion batteries (NIBs) and potassium-ion batteries (KIBs). The cyclic stability test analysis indicates that in the initial cycle, the MoS NIB demonstrates exceptional performance, with a peak charge capacity of 1056 mAh g, while retaining high Coulombic efficiency. However, the WS KIB underperforms, with the least charge capacity of 130 mAh g in the first cycle and exceptionally low retention at a current density of 100 mA g. The MoWS TMD alloy exhibits a moderate charge capacity and cyclic efficiency for both NIBs and KIBs. This comparison study shows that decreasing sizes of alkali-metal ions and constituent elements in TMDs or TMD alloys leads to decreased resistance and slower degradation processes as indicated by cyclic voltammetry and electrochemical impedance spectroscopy after 10 cycles. Furthermore, the study of probable electrochemical intercalation and removal processes of Na-ions and K-ions demonstrates that large geometrically shaped TMD flakes are more responsive to intercalation for Na-ions than K-ions. These performance comparisons of different TMD materials for NIBs and KIBs may promote the future development of these batteries.
PubMed: 38882118
DOI: 10.1021/acsomega.4c01966 -
International Journal of Biological... Jun 2024Ethyl cellulose (EC)-based composite sponges were developed for oil spillage treatment. The EC sponge surface was decorated with helical carbon nanotubes (HCNTs) and...
Ethyl cellulose (EC)-based composite sponges were developed for oil spillage treatment. The EC sponge surface was decorated with helical carbon nanotubes (HCNTs) and molybdenum disulfide (MoS) (1 phr) using the inside-out sugar templating method. The inside surface of a sugar cube was coated with HCNTs and MoS. After filling the sugar cube pores with EC and the subsequent sugar leaching, the decorating materials presented on the sponge surface. The EC/HCNT/MoS sponge had a high level of oil removal based on its adsorption capacity (41.68 g/g), cycled adsorption (∼75-79 %), separation flux efficiency (∼85-95 %), and efficiency in oil/water emulsion separation (92-94 %). The sponge maintained adsorption capacity in acidic, basic, and salty conditions, adsorbed oil under water, and functioned as an oil/water separator in a continuous pump-assisted system. The compressive stress and Young's modulus of the EC sponge increased following its decoration using HCNTs and MoS. The composite sponge was robust based on cycled compression and was thermally stable up to ∼120 C. Based on the eco-friendliness of EC, the low loading of HCNTs and MoS, and sponge versatility, the developed EC/HCNT/MoS sponge should be good candidate for use in sustainable oil adsorption and separation applications.
PubMed: 38880452
DOI: 10.1016/j.ijbiomac.2024.133119 -
Talanta Jun 2024In this work, a novel molecularly imprinted electrochemical aptasensor (MIEAS) was developed for highly selective detection of dexamethasone (Dex) in natural water...
In this work, a novel molecularly imprinted electrochemical aptasensor (MIEAS) was developed for highly selective detection of dexamethasone (Dex) in natural water environment. Gold nanoparticles (AuNPs) modified by nitrogen doped molybdenum carbide-graphene (N-MoC-Gr) were employed as the supports, where N-MoC-Gr improved the conductivity of the electrode and provided a larger specific surface area to polymerize more active substances. Using Dex as template molecule, o-phenylenediamine (o-PD) as the chemical functional monomer and aptamer as the biofunctional monomer, a molecularly imprinted polymer (MIP) membrane with Dex specific recognition sites was formed by electropolymerization. Due to the synergistic effect of MIP and aptamers, the as-prepared MIEAS exhibited a decent linear relationship to Dex detection within a relatively wide range of 10 - 10 M, and the detection limit was 1.79 × 10 M. The recovery in actual water and tablet samples is satisfactory, which confirms the potential application prospects of this sensor in the determination of Dex.
PubMed: 38879945
DOI: 10.1016/j.talanta.2024.126404 -
The Science of the Total Environment Sep 2024The characteristics of radon exhalation in the hygroscopic properties of powder solid wastes are immensely significant for environmental safety and their transportation,...
The characteristics of radon exhalation in the hygroscopic properties of powder solid wastes are immensely significant for environmental safety and their transportation, storage, and landfill. This study detected the radon concentration of superfine cement and five kinds of powder solid waste: fly ash, silica fume, coal gangue, S95 mineral powder, and molybdenum tailing powder, at different hygroscopic times for 1-5 d under 95 % relative humidity. Additionally, the influence of particle size and porosity of solid waste on radon exhalation characteristics was analyzed using a laser particle size analyzer and nitrogen adsorption technology. The results show that the radon exhalation rate of the solid waste was at a low level in dry conditions. Although the presence of water due to the increased moisture absorption rate inhibited the radon exhalation to a certain extent, it was higher than that in dry conditions. The reciprocal of the moisture absorption rate had a strong linear relationship with the ratio between the radon exhalation rate after hygroscopy and radon exhalation rate from dry materials. The pore structure has a significant effect on the exhalation rate of radon, and the macropores inhibits the exhalation rate of radon. The results of this study have guiding significance for the reuse of solid waste and the prevention of radiation risk of radon exhalation during transportation.
PubMed: 38879029
DOI: 10.1016/j.scitotenv.2024.173956