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Rice blast, caused by the filamentous fungus Pyricularia oryzae, has long been one of the major threats to almost all rice-growing areas worldwide. Metconazole, 5-(4-chlorobenzyl)-2, 2-dimethyl-1-(1H-1, 2, 4-triazol-1-ylmethyl) cyclopentanol, is a lipophilic, highly active triazole fungicide that has been applied in the control of various fungal pathogens of crops (cereals, barley, wheat), such as the Fusarium and Alternaria species. However, the antifungal activity of metconazole against P. oryzae is unknown. In this study, metconazole exhibited broad spectrum antifungal activities against seven P. oryzae strains collected from rice paddy fields and the wild type strain P131. Scanning electron microscopic analysis and fluorescein diacetate staining assays revealed that metconazole treatment damaged the cell wall integrity, cell membrane permeability and even cell viability of P. oryzae, resulting in deformed and shrunken hyphae. The supplementation of metconazole in vitro increased fungal sensitivity to different stresses, such as sodium dodecyl sulfate, congo red, sodium chloride, sorbitol and oxidative stress (H2O2). Metconazole could inhibit key virulence processes of P. oryzae, including conidial germination, germ tube elongation and appressorium formation. Furthermore, this chemical prevented P. oryzae from infecting barley epidermal cells by disturbing appressorium penetration and subsequent invasive hyphae development. Pathogenicity assays indicated a reduction of over 75% in the length of blast lesions in both barley and rice leaves when 10 μg/mL of metconazole was applied. This study provides evidence to understand the antifungal effects of metconazole against P. oryzae and demonstrates its potential in rice blast management. [ABSTRACT FROM AUTHOR]

The rare-earth oxide nanoparticles along carbon nanotubes (CNTs) (M2O3/CNTs, M = Y, Nd, Sm) were prepared by in situ solvothermal method. Products were characterized by infrared spectroscopy, X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectrometry, scanning electron microscopy, and Brunauer-Emmett-Teller method. M2O3/CNTs presented good morphology and large surface area. Furthermore, catalysis of M2O3/CNTs during the thermal decomposition of ammonium perchlorate (AP) was evaluated by differential thermal analysis (DTA). Compared with Nd2O3/CNTs and Sm2O3/CNTs, Y2O3/CNTs nanocomposites showed the best catalytic effect on the thermal decomposition of AP. With the addition of 2 wt.% Y2O3/CNTs nanocomposite, high decomposition temperature of AP decreased by 125.5°C, and the total DTA heat release increased by 2.027 kJ·g−1. [ABSTRACT FROM AUTHOR]

Xylella fastidiosa causes Pierce's disease (PD) on grapevines, leading to significant economic losses in grape and wine production. To further our understanding of X. fastidiosa virulence on grapevines, we examined the PD1311 gene, which encodes a putative acyl-coenzyme A (acyl-CoA) synthetase, and is highly conserved across Xylella species. It was determined that PD1311 is required for virulence, as the deletion mutant, ΔPD1311, was unable to cause disease on grapevines. The ΔPD1311 strain was impaired in behaviours known to be associated with PD development, including motility, aggregation and biofilm formation. ΔPD1311 also expressed enhanced sensitivity to H2O2 and polymyxin B, and showed reduced survival in grapevine sap, when compared with wild-type X. fastidiosa Temecula 1 (TM1). Following inoculation, ΔPD1311 could not be detected in grape shoots, which may be related to its altered growth and sensitivity phenotypes. Inoculation with ΔPD1311 2 weeks prior to TM1 prevented the development of PD in a significant fraction of vines and eliminated detectable levels of TM1. In contrast, vines inoculated simultaneously with TM1 and ΔPD1311 developed disease at the same level as TM1 alone. In these vines, TM1 populations were distributed similarly to populations in TM1-only inoculated plants. These findings suggest that, through an indirect mechanism, pretreatment of vines with ΔPD1311 suppresses pathogen population and disease. [ABSTRACT FROM AUTHOR]

Xylella fastidiosa is a xylem-limited bacterium in plant hosts and causes Pierce’s disease (PD) of grapevines, which differ in susceptibility according to the Vitis species (spp.). In this work we compared X. fastidiosa biofilm formation and population dynamics when cultured in xylem saps from PD-susceptible and -resistant Vitis spp. under different conditions. Behaviors in a closed-culture system were compared to those in different sap-renewal cultures that would more closely mimic the physicochemical environment encountered in planta. Significant differences in biofilm formation and growth in saps from PD-susceptible and -resistant spp. were only observed using sap renewal culture. Compared to saps from susceptible V. vinifera, those from PD-resistant V. aestivalis supported lower titers of X. fastidiosa and less biofilm and V. champinii suppressed both growth and biofilm formation, behaviors which are correlated with disease susceptibility. Furthermore, in microfluidic chambers X. fastidiosa formed thick mature biofilm with three-dimensional (3-D) structures, such as pillars and mounds, in saps from all susceptible spp. In contrast, only small aggregates of various shapes were formed in saps from four out of five of the resistant spp.; sap from the resistant spp. V. mustangensis was an exception in that it also supported thick lawns of biofilm but not the above described 3-D structures typically seen in a mature biofilm from the susceptible saps. Our findings provide not only critical technical information for future bioassays, but also suggest further understanding of PD susceptibility. [ABSTRACT FROM AUTHOR]

For achieving successful chemotherapy against cancer, designing biocompatible drug delivery systems (DDSs) with long circulation times, high cellular endocytosis efficiency, and targeted drug release is of upmost importance. Herein, a well-defined PEG-b-P(MASSChol-co-MANBoc) block copolymer bearing redox-sensitive cholesteryl-side group was prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization (with non-redox PEG-b-P(MACCChol-co-MAN-DCA) as the reference), and 1,2-dicarboxylic-cyclohexene acid (DCA) was then grafted onto the hydrophobic block to endow it with charge-convertible characteristics under a tumor microenvironment. The amphiphilic copolymer could be assembled into polymeric spherical micelles (SSMCs) with polyethylene glycol (PEG) as the corona/shell, and anti-cancer drug doxorubicin (DOX) was successfully encapsulated into the micellar core via strong hydrophobic and electrostatic interactions. This nanocarrier showed high stability in the physiological environment and demonstrated "smart" surface charge conversion from negative to positive in the slightly acidic environment of tumor tissues (pH 6.5~6.8), as determined by dynamic light scattering (DLS). Moreover, the cleavage of a disulfide bond linking the cholesterol grafts under an intracellular redox environment (10 mM GSH) resulted in micellar dissociation and accelerated drug release, with the non-redox-responsive micelles (CCMCs) as the control. Additionally, a cellular endocytosis and tumor proliferation inhibition study against MCF-7 tumor cells demonstrated the enhanced endocytosis and tumor cell inhibitory efficiency of dual-responsive SSMCs/DOX nanomedicines, revealing potentials as multifunctional nanoplatforms for effective oncology treatment. [ABSTRACT FROM AUTHOR]

The major drawback of flexible Cu 2 ZnSn(S,Se) 4 (CZTSSe) solar cells is the inevitable residual stress in CZTSSe that considerably limits the efficiency and flexibility of these cells. Hence, in this work, TiN layers with varying thicknesses were sputtered between flexible Ti substrates and back contact Mo layers as diffusion barriers. The TiN barrier layer relieved residual stress, facilitated grain growth, and decreased the porosity of CZTSSe, thereby effectively suppressing the formation of carrier recombination paths and improving the mechanical strength of CZTSSe. Meanwhile, the band alignment of the CZTSSe/CdS heterojunction could be significantly tailored, leading to an improved "cliff-like" conduction band offset from −0.49 eV to −0.33 eV. Under the optimized TiN layer thickness of 50 nm, the power conversion efficiency of the fabricated flexible CZTSSe solar cell increased considerably from 3.43% to 4.85% along with high bending stability. Therefore, introducing the TiN diffusion barrier into traditional flexible CZTSSe solar cells improves the efficiency and flexibility of these devices. Moreover, this method could be a promising pathway for the large-scale production of smart, flexible, and portable electronic devices. [ABSTRACT FROM AUTHOR]

It is essential to design multifunctional contact lenses for selective recognition and utilization of the eye drop ofloxacin (OFL). Modified silicone hydrogel (MSL) contact lenses were firstly synthesized via ultraviolet curing by using (hydroxymethyl)methyl aminomethane, polydimethylsiloxane, methacryloxypropyl terminated polydimethylsiloxane, and N,N-dimethylacrylamide as monomers and N-vinyl-2-pyrrolidinone (NVP) as a modifier. The synthesized MSL contact lenses were characterized via Fourier transform infrared spectroscopy, scanning electron microscopy, and contact angle and mechanical property tests. The results showed that compared with silicone hydrogel (SL) contact lenses, the MSL contact lenses had a more porous structure and good swelling and mechanical properties. The molecularly imprinted polymer/ofloxacin-modified silicone hydrogel (MIP/OFL-MSL) contact lenses were firstly synthesized via free radical polymerization, using ofloxacin (OFL) as the template molecule. Moreover, compared with chlorogenic acid and myricetin molecule, the MIP/OFL-MSL contact lenses exhibited an adsorption capacity for OFL that reached 2.86 mg/g. The antibacterial test showed that the MIP/OFL-MSL contact lenses displayed an inhibition ring size of 15.2 mm and 17.8 mm for Staphylococcus aureus and Escherichia coli, respectively. [ABSTRACT FROM AUTHOR]

Simple Summary: The cashmere industry is a crucial resource and pillar of animal husbandry in the desert and semidesert regions of the central and western Inner Mongolia Autonomous Region. The development of embryonic hair follicles is vital in determining the quality and quantity of cashmere; however, the molecular mechanisms underlying embryonic hair follicle development remain unknown. This study employed proteomic and metabolomic techniques to analyse embryonic skin samples from cashmere goats. The results revealed that the oxytocin signalling pathway is crucial in embryonic hair follicle development by activating the MAPK and Ca2+ signalling pathways. The findings of this study expand our theoretical understanding of embryonic hair follicle development in cashmere goats and serve as a premise for future research. The hair follicle (HF) is the fundamental unit for fleece and cashmere production in cashmere goats and is crucial in determining cashmere yield and quality. The mechanisms regulating HF development in cashmere goats during the embryonic period remain unclear. Growing evidence suggests that HF development involves complex developmental stages and critical events, and identifying the underlying factors can improve our understanding of HF development. In this study, samples were collected from embryonic day 75 (E75) to E125, the major HF developmental stages. The embryonic HFs of cashmere goats were subjected to proteomic and metabolomic analyses, which revealed dynamic changes in the key factors and signalling pathways controlling HF development at the protein and metabolic levels. Gene ontology and the Kyoto Encyclopaedia of Genes and Genomes were used to functionally annotate 1784 significantly differentially expressed proteins and 454 significantly differentially expressed metabolites enriched in different HF developmental stages. A joint analysis revealed that the oxytocin signalling pathway plays a sustained role in embryonic HF development by activating the MAPK and Ca2+ signalling pathways, and a related regulatory network map was constructed. This study provides a global perspective on the mechanism of HF development in cashmere goats and enriches our understanding of embryonic HF development. [ABSTRACT FROM AUTHOR]

Aims: Nerve injury‐induced maladaptive changes in gene expression in the spinal neurons are essential for neuropathic pain genesis. Circular RNAs (ciRNA) are emerging as key regulators of gene expression. Here, we identified a nervous‐system‐tissues‐specific ciRNA‐Kat6 with conservation in humans and mice. We aimed to investigate whether and how spinal dorsal horn ciRNA‐Kat6b participates in neuropathic pain. Methods: Unilateral sciatic nerve chronic constrictive injury (CCI) surgery was used to prepare the neuropathic pain model. The differentially expressed ciRNAs were obtained by RNA‐Sequencing. The identification of nervous‐system‐tissues specificity of ciRNA‐Kat6b and the measurement of ciRNA‐Kat6b and microRNA‐26a (miRNA‐26a) expression level were carried out by quantitative RT‐PCR. The ciRNA‐Kat6b that targets miRNA‐26a and miRNA‐26a that targets Kcnk1 were predicted by bioinformatics analysis and verified by in vitro luciferase reports test and in vivo experiments including Western‐blot, immunofluorescence, and RNA–RNA immunoprecipitation. The correlation between neuropathic pain and ciRNA‐Kat6b, miRNA‐26a, or Kcnk1 was examined by the hypersensitivity response to heat and mechanical stimulus. Results: Peripheral nerve injury downregulated ciRNA‐Kat6b in the dorsal spinal horn of male mice. Rescuing this downregulation blocked nerve injury‐induced increase of miRNA‐26a, reversed the miRNA‐26a‐triggered decrease of potassium channel Kcnk1, a key neuropathic pain player, in the dorsal horn, and alleviates CCI‐induced pain hypersensitivities. On the contrary, mimicking this downregulation increased the miRNA‐26a level and decreased Kcnk1 in the spinal cord, resulting in neuropathic pain‐like syndrome in naïve mice. Mechanistically, the downregulation of ciRNA‐Kat6b reduced the accounts of miRNA‐26a binding to ciRNA‐Kat6b, and elevated the binding accounts of miRNA‐26a to the 3′ untranslated region of Kcnk1 mRNA and degeneration of Kcnk1 mRNA, triggering in the reduction of KCNK1 protein in the dorsal horn of neuropathic pain mice. Conclusion: The ciRNA‐Kat6b/miRNA‐26a/Kcnk1 pathway in dorsal horn neurons regulates the development and maintenance of neuropathic pain, ciRNA‐Kat6b may be a potential new target for analgesic and treatment strategies. [ABSTRACT FROM AUTHOR]

This study synthesized poly(vinyl alcohol)/carboxymethyl chitosan/cyanidin (PVA/CMCS/CY) hydrogel films. First, PVA and CMCS were used to synthesize hydrogel films by ultraviolet irradiation. Meanwhile, CY was in situ combined into the hydrogel films through the electrostatic attraction between CMCS and CY. Next, the products were analyzed using Fourier-transform infrared spectroscopy, scanning electron microscopy, contact angle test, swelling analysis, and mechanical property test. The results revealed that compared with PVA/CMCS hydrogel films, the PVA/CMCS/CY hydrogel films had an interporous structure and good swelling and mechanical properties. Moreover, the drug release experiments demonstrated that the PVA/CMCS/CY hydrogel films had a CY encapsulation efficiency of 33.5% with a sustained CY release of up to 60 h. Furthermore, the examined antibacterial activities against Staphylococcus aureus and Escherichia coli showed that the porous PVA/CMCS/CY hydrogel films exhibited a certain inhibition. Cell viability experiments demonstrated that the PVA/CMCS/CY films displayed no obvious cytotoxicity to human umbilical vein endothelial cells. [ABSTRACT FROM AUTHOR]

The Fe3O4/reduced graphene oxide (Fe3O4/RGO) nanocomposites with good dispersibility were synthesized for targeted delivery of paclitaxel (PTX). Firstly, the superparamagnetic Fe3O4/functional GO nanocomposites were prepared via hydrothermal method in which GO sheets were modified by surfactant wrapping. The Fe3O4/RGO nanocomposites were successively prepared through the reduction of graphene oxide. The products were investigated by Fourier-transform infrared spectrum, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, and vibration sample magnetometry. It was found that spherical Fe3O4 nanoparticles were uniformly anchored over the RGO matrix and the nanocomposites were superparamagnetic with saturation magnetization (Ms) of 9.39 emu/g. Then PTX was loaded onto Fe3O4/RGO nanocomposites, and the drug loading capacity was 67.9%. Cell viability experiments performed on MCF-7 demonstrated that the Fe3O4/RGO-loaded PTX (Fe3O4/RGO/PTX) showed cytotoxicity to MCF-7, whereas the Fe3O4/RGO displayed no obvious cytotoxicity. The above results indicated that Fe3O4/RGO/PTX nanocomposites had potential application in tumor-targeted chemotherapy. [ABSTRACT FROM AUTHOR]

In this study, a Cu 2 O–Au nanoparticles (NPs) heterojunction catalyst anchored on wood was developed by in situ reduction and hydrothermal treatment, and the properties of the catalyst were systematically characterized. The catalyst exhibited prominent photocatalysis of methyl orange (MO, 0.169 min− 1), and tetracycline (TC, 0.122 min−1) which were degraded completely within 20 min. Even after four recyclings, the efficiency of MO degradation by the catalyst remained at 80%. The natural wood with three-dimensional porous structures acted as a reducing agent and a stabilizer for Au NPs and Cu 2 O, which helped to maintain high performance and reusability. The presence of Au NPs mediated the light-induced electron transfer and enhanced the absorption of visible light for promoting photocatalytic activity. The intermediates of contaminants within the degradation process were characterized by liquid chromatography-mass spectrometry. Additionally, the photogenerated superoxide radicals and holes were identified by electron spin resonance. Thus, the potential degradation mechanism catalyzed by the Cu 2 O–Au NPs-wood was proposed. This findings of this study valorizes biomass as a photocatalyst for wastewater remediation. Preparation of a heterogeneous Cu 2 O–Au NPs-wood photocatalyst and its application. [Display omitted] • Cu 2 O–Au NPs-wood heterojunction exhibits highly catalytic property. • Conductive porous carbonized wood enhances the photocatalytic performance. • Cu 2 O–Au NPs-wood can effectively photocatalytic degrade MO and TC. • The degradation of pollutant photo-catalyzed by heterojunction is elucidated. [ABSTRACT FROM AUTHOR]

Simple Summary: Currently, not enough is known about the effect of histone modification on the epigenetic reprogramming of somatic cells, and the lack of basic study limits the development of somatic cell nuclear transfer technology. The aim of this study was to explore the influence of lysine crotonylation, a newly discovered histone post-translational modification, on the reprogramming of somatic cells from Cashmere goats. The results showed that the crotonylation level was increased in somatic cells with sodium crotonate treatment. At the same time, the treatment of somatic cells improved the cloned embryo cleavage rate. In conclusion, an increasing crotonylation level could promote the reprogramming of somatic cells and cloned embryo development. This finding provides an important reference for future improvements in the efficiency of in vitro Cashmere goat somatic cell nuclear transfer embryo production. Failure in the epigenetic reprogramming of somatic cells is considered the main reason for lower cloned embryo development efficiency. Lysine crotonylation (Kcr) occupies an important position in epigenetic modification, while its effects on somatic cell reprogramming have not been reported. In this study, we detected the influence of sodium crotonate (NaCr) on the Kcr levels in three types of somatic cells (muscle-derived satellite cells, MDSCs; fetal fibroblast cells, FFCs; and ear tip fibroblast cells, EFCs). The three types of somatic cells were treated with NaCr for cloned embryo construction, and the cleavage rates and Kcr, H3K9cr, and H3K18cr levels in the cloned embryos were analyzed. The results showed that the abnormal levels of Kcr, H3K9cr, and H3K18cr were corrected in the treatment groups. Although there was no significant difference in the cloned embryo cleavage rate in the FFC treatment group, the cleavage rates of the cloned embryos in the MDSCs and EFCs treatment groups were increased. These findings demonstrated that the Kcr level was increased with NaCr treatment in somatic cells from Cashmere goat, which contributed to proper reprogramming. The reprogramming of somatic cells can be promoted and cloned embryo development can be improved through the treatment of somatic cells with NaCr. [ABSTRACT FROM AUTHOR]

Abstract: By using a surface-modified templating method, Fe2O3@polypyrrole (PPy) core/shell spindles have been successfully prepared in this paper. The Fe2O3 particles with spindle morphology were initially fabricated as core materials. After the PVP modification, the Fe2O3 spindles were subsequently coated with a tunable thickness layer of PPy by in situ deposition of the conducting polymer from aqueous solution. Hollow PPy spindles were produced by dissolution of the Fe2O3 core from the core/shell particles. High-temperature treatment under vacuum condition covert the hollow PPy spindles into carbon capsules by carbonization of the PPy shell. Transmission electron microscope (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS) confirmed the formation of the Fe2O3@PPy core/shell particles, PPy and carbon capsules with spindle morphology. [Copyright &y& Elsevier]

The high hydrophilicity of alginate materials makes delivering a high load of hydrophobic drug difficult. To overcome this drawback, sodium alginate (SA) was modified using octylamine (OA), and then kaempferol (KP) was combined with the alginate solution through the hydrophobic interaction between OA and KP. The modified SA/KP (MSA/KP) hydrogel films were ionically cross-linked by immersing in calcium chloride solution. Subsequently, the products were analyzed via Fourier transform infrared spectroscopy, scanning electron microscopy, contact angle test, thermogravimetric analysis, swelling analysis, water vapor transmission, and mechanical property test. Results showed that compared with the SA hydrogel films, the MSA/KP hydrogel films exhibited an interporous structure, good swelling, and mechanical properties. Moreover, the drug release experiments demonstrated that the MSA/KP hydrogel films achieved a KP encapsulation efficiency of 70.4%, with a sustained KP release of up to 80 h. The cell viability experiments demonstrated that the MSA/KP hydrogel films posed no evident cytotoxicity to human umbilical vein endothelial cells. [ABSTRACT FROM AUTHOR]

Soft actuators with large deformation and high stability in response to multi-stimuli are highly demanded in biomimetic applications. However, most of the present actuators driven by a single stimulus often exhibit low performance and high energy consumption. In this work, a sandwich structural soft actuator (MPDMS/MXene/PTFE) which possesses electrothermal/magnetic coupling actuation is fabricated by combining magnetic NdFeB/Polydimethylsiloxane (MPDMS) composite layer, MXene film, and PTFE tape together. Due to the large difference of thermal expansion coefficient between MPDMS film and PTFE tape, the soft actuator shows a wonderful electrothermal actuation and the bending deformation can reach to as high as 353° under a 3 V power supply. The excellent electrical conductivity of MXene component endows the sandwich film with good thermal management performance, thus the soft MPDMS/MXene/PTFE sandwich films can be applied in the thermal treatment of body and thermal imaging. Most importantly, the soft actuator also exhibits a typical magnetic biomimetic actuation and the programmable actuation performance of the dragonfly actuator can be demonstrated by both experiments and finite element simulations. Eventually, the electrothermal/magnetic coupling actuation is successfully applied in an intelligent crawling robot to overcome the traditional inchworm movement simulation. A dual-mode biomimetic soft actuator based on MPDMS/MXene/PTFE with excellent electrothermal and magnetic drive performance is developed. The soft actuator enables to prepare grippers for transferring objects and assemble the wings of a biomimetic dragonfly in a magnetic field. Finally, a crawling robot is developed to demonstrate the electrothermal/magnetic coupling actuation. [Display omitted] • The highlight of this work is: • The MPDMS/MXene/PTFE soft actuator presents both electrothermal and magneto-actuated deformation behaviors. • The soft actuator shows a wonderful electrothermal actuation and the bending deformation can reach to as high as 353° under a 3 V power supply. • The finite element analysis model can provide design guidance for the deformation process of bionic actuator with complex structure. • The soft actuator strategy presented in this paper is expected to be useful for the development of bionic intelligent actuators with multi-stimulus response. [ABSTRACT FROM AUTHOR]

Local surface plasmon resonance (LSPR) of noble metal nanoparticles plays a significant role in nanocatalysis via directly harvesting optical energy from resonant light. However, the photothermally-assistant catalytic application is limited due to the narrow visible/infrared absorption range and low photothermal conversion efficiency. Herein, a sandwich-structured MXene@Au/Polydopamine (PDA) nanosheet with good hydrophilicity, large specific surface area and tri-photothermal components is developed for nanocatalysis. The Au/PDA hybrid shells are covered on the MXene nanosheets via a simple one-step redox-oxidize polymerization method. As a result, the catalytic dynamic of MXene@Au/PDA nanosheets on reducing 4-nitrophenol reaches to 0.28 min−1·mg−1, which is about 2 times larger than that of the nanocatalysts without NIR light irradiation. Owing to the well protection of PDA shell, after 10 cycles of reduction of 4-nitrophenol, MXene@Au/PDA nanosheets still maintain more than 90% activity. This work in depth insights into NIR light-assistant avenue to enhance the catalytic activity of noble metal nanocatalysts and highlights an easy synthetic model for heterogeneous catalysts based on MXene nanocomposites. An MXene@Au/PDA nanosheet with sandwiched nanostructure has been rationally fabricated by a simple in situ redox-oxidizing polymerization method. Under the irradiation of near-infrared light, the catalytic dynamic of the MXene@Au/PDA nanosheet is excitingly improved by 2 times, thus shows a typical photothermal-enhanced catalytic activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Local surface plasmon resonance (LSPR) of noble metal nanoparticles plays a significant role in nanocatalysis via directly harvesting optical energy from resonant light. However, the photothermally-assistant catalytic application is limited due to the narrow visible/infrared absorption range and low photothermal conversion efficiency. Herein, a sandwich-structured MXene@Au/Polydopamine (PDA) nanosheet with good hydrophilicity, large specific surface area and tri-photothermal components is developed for nanocatalysis. The Au/PDA hybrid shells are covered on the MXene nanosheets via a simple one-step redox-oxidize polymerization method. As a result, the catalytic dynamic of MXene@Au/PDA nanosheets on reducing 4-nitrophenol reaches to 0.28 min−1·mg−1, which is about 2 times larger than that of the nanocatalysts without NIR light irradiation. Owing to the well protection of PDA shell, after 10 cycles of reduction of 4-nitrophenol, MXene@Au/PDA nanosheets still maintain more than 90% activity. This work in depth insights into NIR light-assistant avenue to enhance the catalytic activity of noble metal nanocatalysts and highlights an easy synthetic model for heterogeneous catalysts based on MXene nanocomposites. An MXene@Au/PDA nanosheet with sandwiched nanostructure has been rationally fabricated by a simple in situ redox-oxidizing polymerization method. Under the irradiation of near-infrared light, the catalytic dynamic of the MXene@Au/PDA nanosheet is excitingly improved by 2 times, thus shows a typical photothermal-enhanced catalytic activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Therapeutic ophthalmic contact lenses with prolonged drug release and improved bioavailability have been developed to circumvent tedious eye drop instillation. In this work, zwitterionic nanogels based on poly(sulfobetaine methacrylate) (PSBMA) were easily fabricated by one-step reflux-precipitation polymerization, with the advantages of being surfactant-free and morphology controlled. Then, the ophthalmic drug levofloxacin (LEV) was encapsulated into the nanogels. A set of contact lenses with varied nanogel-loading content was fabricated by the cast molding method, with the drug-loaded nanogels dispersed in pre-monomer solutions composed of 2-hydroxyethyl methacrylate (HEMA) and N-vinyl-2-pyrrolidone (NVP). The structure, surface morphology, water contact angle (WCA), equilibrium water content (EWC), transmittance, and mechanical properties of the contact lenses were subsequently investigated, and in vitro drug release and biocompatibility were further evaluated. As a result, the optimized contact lens with nanogel-loading content of 8 wt% could sustainably deliver LEV for ten days, with critical lens properties within the range of recommended values for commercial contact lenses. Moreover, cell viability assays revealed that the prepared contact lenses were cytocompatible, suggesting their significant potential as an alternative to traditional eye drops or ointment formulations for long-term oculopathy treatment. [ABSTRACT FROM AUTHOR]

• Fe 3 O 4 @Au/PDA hollow nanosphere is prepared by a facile one-step method. • H-Fe 3 O 4 @Au/PDA can simultaneously treat the toxic ions and contaminants. • It has good catalytic and adsorption properties for 4-nitrophenol and U (VI). The organic pollutants and heavy metal ions are critical harmful substances in waste water because they destroy the ecological systems and lead diseases to animals and human beings. Unfortunately, the simultaneously remove of them in one system is still a challenge due to their different treating mechanism. Herein, a novel magnetic h-Fe 3 O 4 @Au/Polydopamine (Au/PDA) hybrid hollow nanosphere which can both absorb the potentially toxic U(VI) ions and catalyze the reduction of the 4-nitrophenol is reported. By using a simple in situ redox-oxidizing polymerization method, the h-Fe 3 O 4 hollow nanosphere is well encapsulated by the Au/PDA hybrid shell to form the dual-functional magnetic hollow nanocomposites. Owing to the hollow interior, uniform and functional PDA coating, and high active Au nanocrystals, the final h-Fe 3 O 4 @Au/PDA hollow nanosphere possesses high potential in nanocatalysis, heavy metal ions adsorption, and drug delivery. Because of the PDA protection, the h-Fe 3 O 4 @Au/PDA nanosphere can even keep 90% activity after 7 cycling catalytic reactions on reduction of 4-nitrophenol. Similarly, the h-Fe 3 O 4 @Au/PDA exhibits a good adsorption effect for U(VI) in nuclear waste and its adsorption capability reaches to 82.9 mg·g−1 by 6 successive adsorption–desorption experiments. Due to the facile magnetic separation, the h-Fe 3 O 4 @Au/PDA nanosphere can be easily collected by applying an external magnetic field. In summary, such a multifunctional recyclable h-Fe 3 O 4 @Au/PDA nanosphere with green and facile synthesis, easy manipulation, efficient adsorption performance and good catalytic activity possesses broad application potential in treatment of coexisting toxic water pollution. [ABSTRACT FROM AUTHOR]