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Spinal cord injury (SCI) often results in motor and sensory deficits, or even paralysis. Due to the role of the cascade reaction, the effect of excessive reactive oxygen species (ROS) in the early and middle stages of SCI severely damage neurons, and most antioxidants cannot consistently eliminate ROS at non-toxic doses, which leads to a huge compromise in antioxidant treatment of SCI. Selenium nanoparticles (SeNPs) have excellent ROS scavenging bioactivity, but the toxicity control problem limits the therapeutic window. Here, we propose a synergistic therapeutic strategy of SeNPs encapsulated by ZIF-8 (SeNPs@ZIF-8) to obtain synergistic ROS scavenging activity. Three different spatial structures of SeNPs@ZIF-8 were synthesized and coated with ferrostatin-1, a ferroptosis inhibitor (FSZ NPs), to achieve enhanced anti-oxidant and anti-ferroptosis activity without toxicity. FSZ NPs promoted the maintenance of mitochondrial homeostasis, thereby regulating the expression of inflammatory factors and promoting the polarization of macrophages into M2 phenotype. In addition, the FSZ NPs presented strong abilities to promote neuronal maturation and axon growth through activating the WNT4-dependent pathways, while prevented glial scar formation. The current study demonstrates the powerful and versatile bioactive functions of FSZ NPs for SCI treatment and offers inspiration for other neural injury diseases., (© 2024. The Author(s).)

2,2-bis(chloromethyl) trimethylene bis[bis(2-chloroethyl) phosphate] (V6) has been widely used as an additive in a variety of plastics due to its extremely low toxicity. However, we showed in the study that once mixed with nanopolystyrene particles (NPs), the nontoxic V6 could exhibit significant toxicity to HeLa cells. The enhanced toxicity was much higher than the toxicity of NPs alone and was related to the size of NPs. The mixture of V6 and small polystyrene NPs (10 nm and 15 nm in radius) showed obvious toxicity to HeLa cells. The toxicity increased with the concentrations of both V6 and NPs. On the contrary, the mixture of V6 and larger NPs (25 nm, 50 nm, 100 nm, and 500 nm in radius) showed almost no toxicity even at extremely high concentrations (NPs: 100 mg/L; V6: 50 mg/L). The small NPs could enter the cells and accumulated in cytoplasm. However, the larger NPs did not distribute inside the cells. NPs efficiently adsorbed V6 on the surface. The mechanism of the enhanced toxicity was attributed to the increased intracellular reactive oxygen species (ROS) production and the regulation of gene expression concerning apoptosis and ROS scavenging. Our study not only showed that a safe chemical V6 could be turned to be toxic by NPs, but also pointed out a potential risk caused by the joint toxicity of 'safe' chemicals and plastic particles with small size.

Baicalin (BA)-berberine (BBR) have been proposed as the couple in the prevention and treatment of numerous diseases due to their multiple functional attributes. However, with regard to certain factors involving unsatisfactory aqueous solubility and low bioavailability associated with its clinical application, there is need for continuous researches by scientist. In this study, after successfully preparing BA-BBR complex, BA-BBR complex nanocrystals were obtained through high-pressure homogenization and evaluated (in vitro and in vivo). The particle size, distribution, morphology, and crystalline properties for the optimal BA-BBR complex nanocrystals were characterized by the use of scanning electron microscope, dynamic light scattering, powder X-ray diffraction, and differential scanning calorimetry. The particle size and poly-dispersity index of BA-BBR complex nanocrystals were 318.40 ± 3.32 nm and 0.26 ± 0.03, respectively. In addition, evaluation of the in vitro dissolution extent indicated that BA and BBR in BA-BBR complex nanocrystals were 3.30- and 2.35-fold than BA-BBR complex. Subsequently, single-pass intestinal perfusion combined with microdialysis test and oral pharmacokinetics in SD rats was employed to evaluate the in vivo absorption improvement of BA-BBR complex nanocrystals. The pharmacokinetics results exhibited that the area under curve of BA and BBR in the BA-BBR complex nanocrystals group were 622.65 ± 456.95 h·ng/ml and 167.28 ± 78.87 h·ng/ml, respectively, which were separately 7.49- and 2.64-fold than the complex coarse suspension. In conclusion, the above results indicate that the developed and optimized BA-BBR complex nanocrystals could improve the dissolution rate and extent and oral bioavailability, as well as facilitate the co-absorption of the drug prescriptions BA and BBR., (© 2022. Controlled Release Society.)

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver. The majority of patients with HCC are diagnosed with advanced-stage disease. Sorafenib is a frontline therapy drug approved by the Food and Drug Administration for advanced HCC. However, the poor aqueous solubility of sorafenib limits its applications. The present study aimed to overcome this limitation of sorafenib. Thus, bovine serum albumin (BSA)-based nanoparticles were developed to encapsulate hydrophobic sorafenib. The resultant sorafenib-loaded BSA nanoparticles (Sf-BSA-NPs) were thoroughly characterized for size distribution, encapsulation efficiency and morphology. Previous studies on HepG2 cells in vitro have demonstrated that Sf-BSA-NPs exhibit remarkable superiority to free sorafenib in cytocompatibility, cytotoxicity and proapoptotic effect. The results of the present study demonstrated that Sf-BSA-NPs were effective in improving aqueous solubility, and enhanced drug cytotoxicity, suggesting its therapeutic potential for HCC.

In order to achieve safe and high-efficient photodynamic therapy (PDT), it was a powerful strategy of constructing O 2 -generated nanozyme with intelligent "off/on" modulation and enhancement. Herein, a kind of H 2 O 2 -responsive nanozyme was developed for off/on modulation and enhancement of magnetic resonance (MR) imaging and PDT, in which great amounts of gold nanoclusters (AuNCs) were loaded into mesoporous silica to form nanoassembly, and manganese dioxide (MnO 2 ) nanosheets were wrapped as switching shield shell (AuNCs@mSiO 2 @MnO 2 ). In a neutral physiological environment, stable MnO 2 shells eliminated singlet oxygen ( 1 O 2 ) generation to switch off PDT and MR imaging. However, in an acidic tumor microenvironment, the MnO 2 shell reacted with H 2 O 2 , in which MnO 2 degradation switched on MR imaging and PDT, and the generated O 2 further enhanced PDT. H 2 O 2 -responsive MnO 2 degradation brought about excellent MR imaging with a longitudinal relaxation rate of 25.31 mM -1 s -1 , and simultaneously sufficient O 2 generation guaranteed a 74% high 1 O 2 yield. Under the irradiation of a 635 nm laser, the viability of MDA-MB-435 cells was reduced to 4%, and the tumors completely disappeared, demonstrating strong PDT performance. Therefore, H 2 O 2 -responsive AuNCs@mSiO 2 @MnO 2 nanozyme showed excellent off/on modulation and enhancement of MR imaging and PDT and was a promising intelligent nanoprobe for safe and high-efficiency theranostics.

Activation of receptor tyrosine kinase (RTK) protein is frequently observed in malignant progression of gliomas. In this study, the crosstalk activation of epidermal growth factor receptor (EGFR) and mesenchymal-epithelial transition factor (MET) signaling pathways is demonstrated to contribute to temozolomide (TMZ) resistance, resulting in an unfavorable prognosis for patients with glioblastoma. To simultaneously mitigate EGFR and MET activation, a dual functionalized brain-targeting nanoinhibitor, BIP-MPC-NP, is developed by conjugating Inherbin3 and cMBP on the surface of NHS-PEG 8 -Mal modified MPC-nanoparticles. In the presence of BIP-MPC-NP, DNA damage repair is attenuated and TMZ sensitivity is enhanced via the down-regulation of E2F1 mediated by TTP in TMZ resistant glioma. In vivo magnetic resonance imaging (MRI) shows a significant repression in tumor growth and a prolonged survival of mice after injection of the BIP-MPC-NP and TMZ. These results demonstrate the promise of this nanoinhibitor as a feasible strategy overcoming TMZ resistance in glioma.

Background: Cancer stem cells (CSCs) are highly proliferative and tumorigenic, which contributes to chemotherapy resistance and tumor occurrence. CSCs specific therapy may achieve excellent therapeutic effects, especially to the drug-resistant tumors., Results: In this study, we developed a kind of targeting nanoparticle system based on cationic albumin functionalized with hyaluronic acid (HA) to target the CD44 overexpressed CSCs. All-trans-retinoic acid (ATRA) was encapsulated in the nanoparticles with ultrahigh encapsulation efficiency (EE%) of 93% and loading content of 8.37%. TEM analysis showed the nanoparticles were spherical, uniform-sized and surrounded by a coating layer consists of HA. Four weeks of continuously measurements of size, PDI and EE% revealed the high stability of nanoparticles. Thanks to HA conjugation on the surface, the resultant nanoparticles (HA-eNPs) demonstrated high affinity and specific binding to CD44-enriched B16F10 cells. In vivo imaging revealed that HA-eNPs can targeted accumulate in tumor-bearing lung of mouse. The cytotoxicity tests illustrated that ATRA-laden HA-eNPs possessed better killing ability to B16F10 cells than free drug or normal nanoparticles in the same dose, indicating its good targeting property. Moreover, HA-eNPs/ATRA treatment decreased side population of B16F10 cells significantly in vitro. Finally, tumor growth was significantly inhibited by HA-eNPs/ATRA in lung metastasis tumor mice., Conclusions: These results demonstrate that the HA functionalized albumin nanoparticles is an efficient system for targeted delivery of antitumor drugs to eliminate the CSCs.

A co-loaded drug delivery system based on ascorbyl palmitate that can transport various functional drugs to their targets within a tumor represents an attractive strategy for increasing the efficiency of anticancer treatment. In this study, we developed a dual drug delivery system to encapsulate ascorbyl palmitate (AP) and paclitaxel (PTX) for synergistic cancer therapy. AP, which is a vitamin C derivative, and PTX were incorporated into solid lipid nanoparticles (AP/PTX-SLNs), which were used to treat murine B16F10 melanoma that had metastasized to the lungs of mice. These nanoparticles were spherical with an average size of 223 nm as measured by transmission electron microscope and dynamic light scattering. In vitro cytotoxicity assays indicated that the AP/PTX-SLNs with an AP/PTX mass ratio of 2/1 provided the optimal synergistic anticancer efficacy. In vivo, AP/PTX-SLNs were revealed to be much more effective in suppressing tumor growth in B16F10-bearing mice and in eliminating cancer cells in the lungs than single drug (AP or PTX)-loaded SLNs via a synergistic effect through reducing the Bcl-2/Bax ratio. Furthermore, no marked side effects were observed during the treatment with the AP/PTX-SLNs, indicating that the co-delivery system with ascorbyl palmitate holds promising clinical potential in cancer therapy.

Conventional enhanced permeation and retention (EPR) mediates the effects of many drugs, including the accumulation of nanocarriers at tumor sites, but its efficiency remains low. In this study, this limitation was overcome by developing a dual-targeting delivery system based on hyaluronan (HA, a major ligand of CD44) and tetraiodothyroacetic acid (tetrac, a specific ligand of αvβ3), which was exploited to carry docetaxel (DTX) for the synergistic active targeting to tumors. First, a tetrac-HA (TeHA) conjugate was synthesized and grafted onto the surfaces of solid lipid nanoparticles (SLNs) (TeHA-SLNs/DTX), with a high encapsulation efficiency of >91.6%. The resulting SLNs exhibited an approximately toroid morphology revealed using TEM. The cellular uptake and cytotoxicity of various formulations on CD44/αvβ3-enriched B16F10 cells were then assessed, and both results confirmed the selective uptake and high cytotoxicity of the TeHA-SLNs/DTX in a TeHA-dependent manner. In vivo imaging and vessel distribution tests revealed the efficiency of synergistic active targeting was higher than that of EPR-mediated passive targeting by the TeHA-SLNs to αvβ3-expressing tumor blood vessels and CD44-expressing tumor cells via selective targeting. Finally, in both xenograft tumor mice and in situ lung metastasis tumor mice, tumor growth was significantly inhibited by TeHA-SLNs/DTX. Therefore, TeHA-SLNs are an efficient system for the dual-targeted delivery of drugs to treat cancer in vivo., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The materials with low dielectric constant and low dielectric loss are vital for high integration degree of the circuit board. Although many polymers like epoxy resin exhibit excellent comprehensive performance, their dielectric constant is unable to satisfy high electronic packaging application. In this work, we present a simple grafting strategy via reaction between the hollow glass microsphere and polyhedral oligomeric silsesquioxane followed by blending epoxy resin to fabricate epoxy resin hollow glass microspheres composite materials. The superior heat resistance of hollow glass microspheres (HGM) can improve the thermal performance of composites. Due to the addition of Ge‐POSS, P‐HGM exhibited a good interfacial compatibility with epoxy resin matrix and forms an interfacial adhesion region. With the P‐HGM loading of 20 wt%, the fabricated composite materials exhibited the low dielectric constant of 2.59 and low dielectric loss of 0.0145. At the same time, the tensile strength, impact strength and flexural strength were 42.15 MPa, 24.33 kJ/m2 and 90.82 MPa, respectively, which demonstrated that the epoxy resin hollow glass microspheres composite materials processed superb mechanical behavior. It suggests that this method is a promising potential for fabricating low dielectric composite materials. [ABSTRACT FROM AUTHOR]

Advanced polymer dielectrics with high energy density at elevated temperatures are highly desired to meet the requirements of modern electronic and electrical systems under harsh conditions. Herein, we report a novel polyimide/magnesium oxide (PI/MgO) nanodielectric that exhibits high energy storage density (Ue) and charge–discharge efficiency (η) along with excellent cycling stability at elevated temperatures. Benefiting from the large bandgap of MgO and the extended interchain spacing of PI, the composite films can simultaneously achieve high dielectric constant and high breakdown strength, leading to enhanced energy storage density. The nanocomposite film doped with 0.1 vol% MgO can achieve a maximum Ue of 2.6 J cm−3 and a η of 89% at 450 MV m−1 and 150 °C, which is three times that of the PI film under the same conditions. In addition, embedding ultralow content of inorganic fillers can avoid aggregation and facilitate its large-scale production. This work may provide a new paradigm for exploring polymer nanocomposites with excellent energy storage performance at high temperatures and under a high electric field. [ABSTRACT FROM AUTHOR]

The properties of a reinforced gel with partially hydrolyzed polyacrylamide (HPAM) as the main agent, water-soluble phenolic resin (WSPR) as the crosslinker, and nano-SiO2 as the stabilizer were evaluated in terms of gelation time, gel strength and thermal stability under the conditions of 110 °C and 12.124 g/L salinity in water. The results showed that the gelation time of the gel with high strength was adjustable from 3 to 23 h, remaining stable for more than 180 days under stratigraphic conditions, although with a certain degree of early dehydration in the gel. Cryo-scanning electron microscopy (cryo-SEM) and dynamic light scattering (DLS) analysis revealed that nano-SiO2 improves the dispersion of the polymer in water, resulting in a more homogeneous structure of the formed gel and thus improving the strength of the gels. In addition, rheological tests and cryo-SEM showed that the interaction between nano-SiO2 and the polymer could inhibit the degradation of polymer to a certain extent and improve the thermal stability of the gel. However, the oxidative degradation of the gel is still the main cause of early dehydration of water-soluble phenolic resin gel, and the addition of a small amount of hydroquinone to the gelants can significantly improve the antioxidative degradation properties of phenolic resin gel. [ABSTRACT FROM AUTHOR]

Polycaprolactone-poly (ethylene glycol) block copolymer (PCL-PEG) based nanoparticles were prepared for the intravenous administration of docetaxel (DTX). PCL-PEG-Tyr and PCL-PEG-Ang were synthesized by using tyrosine (Tyr) and angiopep-2 (Ang) as coupling ligands, and dual-modified PCL-PEG-based nanoparticles (PCL-PEG-Tyr/Ang) were prepared. The physicochemical properties, in vitro drug release, in vitro cytotoxicity, in vitro cellular uptake efficiency, in vivo biodistribution and in vivo antitumor efficacy of PCL-PEG-based nanoparticles were investigated. The PCL-PEG-based nanoparticles were spherical with a mean diameter of 100 nm and high encapsulation efficiencies (> 85%). The results of in vitro drug release showed that the PCL-PEG-based nanoparticles loaded with DTX had sustained-release characteristics. For in vitro cytotoxicity tests, the dual-modified PCL-PEG-based nanoparticles (PCL-PEG-Tyr/Ang) demonstrated the minimum IC50 value (2.94 µg/mL) compared with other PCL-PEG-based nanoparticles. In addition, the cellular uptake of coumarin-6 (C6) in HT29 cells was observed and determined in the PCL-PEG-Tyr/Ang nanoparticles group, which was significantly higher than that in the other PCL-PEG-based groups and C6 solution group. The results of in vivo imaging showed that dual-modified PCL-PEG nanoparticles had better tumor targeting than the other PCL-PEG-based nanoparticles. In the HT29 tumor-xenografted nude mice model, DTX-loaded PCL-PEG-Tyr/Ang nanoparticles also had a significantly higher inhibitory efficacy on tumor growth than Taxotere®-treated group. These results indicated that the dual-modified PCL-PEG-based nanoparticles (PCL-PEG-Tyr/Ang) could be a promising anticancer drug delivery system. [ABSTRACT FROM AUTHOR]

Syngas/hydrogen production via hydrocarbon reforming reactions is crucial. Whereas, they need high reaction temperature to obtain economically feasible hydrocarbon conversions, which renders the active and cheap transition metal based catalysts easy to be sintered, leading to the high carbon deposition rate and gradual degradation of catalytic performance. Therefore, developing sintering and carbon resistant catalysts becomes one of the most important issues for these reforming reactions to be industrially applied. Designing catalysts with core/yolk shell structure turns out to be one of the most effective strategies to solve this issue. Herein, recent progress which has been made in the synthesis method for core/yolk shell catalysts with different shell materials such as SiO2, zeolite, CeO2 and Al2O3 is summarized. Additionally, specific applications of these core/yolk catalysts for various hydrocarbon reforming reactions such as dry reforming, steam reforming and methane oxidation are reviewed with the emphasis on revealing the reasons leading to their outstanding catalytic performance. Lastly, possible research directions in core/yolk shell catalysts are proposed. What came first the catalyst or the egg? Designing core/yolk shell structure is one of the most effective measures to prevent sintering of transition metal based catalysts for hydrocarbon reforming reactions, thereby retarding the carbon deposition. [ABSTRACT FROM AUTHOR]

In recent decades, rising anthropogenic greenhouse gas emissions (mainly CO2 and CH4) have increased alarm due to escalating effects of global warming. The dry carbon dioxide reforming of methane (DRM) reaction is a sustainable way to utilize these notorious greenhouse gases. This paper presents a review of recent progress in the development of nickel-based catalysts for the DRM reaction. The enviable low cost and wide availability of nickel compared with noble metals is the main reason for persistent research efforts in optimizing the synthesis of nickel-based catalysts. Important catalyst features for the rational design of a coke-resistant nickel-based nanocatalyst for the DRM reaction are also discussed. In addition, several innovative developments based on salient features for the stabilization of nickel nanocatalysts through various means (which include functionalization with precursors, synthesis by plasma treatment, stabilization/confinement on mesoporous/microporous/carbon supports, and the formation of metal oxides) are highlighted. The final part of this review covers major issues and proposed improvement strategies pertaining to the rational design of nickel-based catalysts with high activity and stability for the DRM reaction. [ABSTRACT FROM AUTHOR]

Ni@Ni-Mgphy(Ni-Mgphy = Ni–Mg phyllosilicate) core–shellcatalysts were designed by hydrothermally treating Ni@SiO2nanoparticles with magnesium nitrate salt. The porosity and basicityof the catalysts were easily tuned by forming Ni-Mgphy shell usingNi originating from Ni@SiO2during the hydrothermal treatmentprocess and Mg(NO3)2as the Ni and Mg sources,respectively. Among Ni@Ni-Mgphy core–shell catalysts synthesizedunder different hydrothermal durations, the catalyst treated for 10h achieved the best catalytic performance for CO2reformingof CH4reaction with stable CO2and CH4conversions of around 81% and 78%, respectively, within 95 h reactionduration at 700 °C. The high Ni accessibility, strong basicity,and high structural stability for Ni@Ni-Mgphy core–shell catalystwith 10 h treatment time accounted for its superb catalytic performance.This method to simultaneously tune the porosity and basicity of Ni@SiO2core–shell nanoparticles demonstrates a general wayto modify the properties of other silica based core–shell nanoparticlesthrough treating them with different metal salts. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of a series of x CeNi-PSNT (phyllosilicate nanotube) oxygen carriers (OCs) and presents the effect of Ce loading on the performance in chemical looping reforming (CLR) of glycerol. Various characterization techniques including N 2 adsorption-desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), H 2 temperature-programmed reduction (TPR), X-ray photoelectron spectra (XPS) and O 2 volumetric chemisorption were employed to investigate the physicochemical properties of the fresh and used OCs. The characterization results demonstrated that the PSNT structure possessed strong confinement effect and that the Ce promotion improved Ni dispersion and the reducibility of NiO particle and isolated Ni ions. The enhanced reducibility significantly shortened the dead time in the fuel feed step, resulting in the high H 2 generation efficiency. The reactivity and stability tests were conducted in a fixed-bed reactor. A Ce/Ni mass ratio of 0.5 was optimized for CLR with an average H 2 yield of 12.5 wt%, an average NiO conversion of 67%, and an accumulated coke deposition of 3.8 wt% in a 10-cycle stability test. The confinement effect of PSNT and Ce promotion both have positive effects on attaining the excellent performance. [ABSTRACT FROM AUTHOR]