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Ultrasound (US) assisted with Fenton (US-Fenton) reaction was developed to efficiently and greenly prepare starch nanoparticles (SNPs) that were employed as nanofillers to enhance gelatin (G) film properties. Compared to Fenton reaction alone, US-Fenton reaction significantly improved preparation efficiency and dispersion of SNPs (p < 0.05). An optimal US-Fenton reaction parameter (300 mM H 2 O 2 , ascorbic acid 55 mM, US 45 min) was found to prepare SNPs with uniform sizes (50–90 nm) and low molecular weight (M n 7.91 × 105 Da). The XRD, FT-IR, and SAXS analysis revealed that the US-Fenton reaction degraded the amorphous and crystalline zones of starch from top to down, leading to the collapse of the original layered structure starch and the progressive formation of SNPs. The different sizes of SNPs were selected to prepare the composite films. The G-SNP3 film (with 50–90 nm SNPs) showed the most outstanding UV blocking, tensile, and barrier properties. Especially, the tensile strength of G-5%SNP3 film (containing 5 % SNPs) increased by 156 % and 6 % over that of G film and G-5%SNP2 film (containing 5%SNPs with 100–180 nm), respectively. Therefore, the nanomaterial was promisingly prepared by the US-Fenton system and provided a strategy for designing and producing nanocomposite films. [Display omitted] • US-Fenton reaction greenly and effectively prepared SNPs (50–90 nm). • The multi-scale structure of SNPs was disrupted by US-Fenton reaction. • Incorporating SNPs enhanced the mechanical and barrier properties of gelatin film. • The tensile strength of G-5%SNP3 film increased by 156 % over that of gelatin film. [ABSTRACT FROM AUTHOR]

Combination of anticancer drugs with therapeutic microRNA (miRNA) has emerged as a promising anticancer strategy. However, the promise is hampered by a lack of desirable delivery systems. We report on the development of self-immolative nanoparticles capable of simultaneously delivering miR-34a mimic and targeting dysregulated polyamine metabolism in cancer. The nanoparticles were prepared from a biodegradable polycationic prodrug, named DSS-BEN, which was synthesized from a polyamine analog N 1 , N 11 -bisethylnorspermine (BENSpm). The nanoparticles were selectively disassembled in the cytoplasm where they released miRNA. Glutathione (GSH)-induced degradation of self-immolative linkers released BENSpm from the DSS-BEN polymers. MiR-34a mimic was effectively delivered to cancer cells as evidenced by upregulation of intracellular miR-34a and downregulation of Bcl-2 as one of the downstream targets of miR-34a. Intracellular BENSpm generated from the degraded nanoparticles induced the expression of rate-limiting enzymes in polyamine catabolism (SMOX, SSAT) and depleted cellular natural polyamines. Simultaneous regulation of polyamine metabolism and miR-34a expression by DSS-BEN/miR-34a not only enhanced cancer cell killing in cultured human colon cancer cells, but also improved antitumor activity in vivo. The reported findings validate the self-immolative nanoparticles as delivery vectors of therapeutic miRNA capable of simultaneously targeting dysregulated polyamine metabolism in cancer, thereby providing an elegant and efficient approach to combination nanomedicines. [ABSTRACT FROM AUTHOR]

Abstract: Lack of safe and effective delivery vehicle is the main obstacle for siRNA mediated cancer therapy. In this study, we synthesized a pH-sensitive polymer of PEG grafted carboxymethyl chitosan (PEG-CMCS) and developed anionic-charged hybrid nanoparticles of PEG-CMCS and calcium phosphate (CaP) for siRNA delivery through a single-step self-assembly method in aqueous condition. The formed nanoparticles with charge of around −8.25 mv and average diameter of 102.1 nm exhibited efficient siRNA encapsulation and enhanced colloidal and serum stability. The test in vitro indicated that the nanoparticles entered into HepG2 cells by endocytosis, and achieved endosomal escape of siRNA effectively due to the pH-responsive disassembly of nanoparticles and dissolution of CaP in the endosome. Reporter gene silencing assay showed that luciferase siRNA delivered by the anionic nanoparticles could achieve gene silencing efficacy comparable to that of conventional Lipofectamine 2000. Additionally, dramatic hTERT knockdown mediated by the anionic nanoparticles transfection induced significant apoptosis of HepG2 cells in vitro. After intravenous injection in tumor-bearing BALB/c nude mice, the nanoparticles specifically accumulated into tumor regions by EPR effect, leading to efficient and specific gene silencing sequentially. Most importantly, the nanoparticles carrying hTERT siRNA inhibited tumor growth significantly via silencing hTERT expression and inducing cells apoptosis in HepG2 tumor xenograft. Moreover, comprehensive safety studies of the nanoparticles confirmed their superior safety both in vitro and in vivo. We concluded that the PEG-CMCS/CaP hybrid anionic nanoparticles possessed potential as a safe and effective siRNA delivery system for anticancer therapy. [Copyright &y& Elsevier]

Abstract: A micro-sized particle Li4Ti5−x La x O12 (0 ≤ x ≤ 0.2) material has been synthesized by a simple solid-state method at air. The obtained Li4Ti5−x La x O12 materials are Li3x La2/3−x TiO3 (LLTO)–Li4Ti5O12 (LTO) solid solution, and well crystallized with a particle size in the range of 1–2 μm. The electronic conductivity and lithium diffusion coefficient of La-modified LTO (Li4Ti4.95La0.05O12) are improved because LLTO exhibits a high ionic conductivity during Li+ extraction. Li4Ti4.95La0.05O12 material shows discharge capacities of more than 206 and 197 mAh g−1 after 100 cycles at 1 C and 3 C charge–discharge rates, respectively. Especially, in rate performance, the Li4Ti5−x La x O12 (x = 0.1, 0.2) samples maintain capacity of about 181 mAh g−1 until 5 C rates after 200 cycles, while the pure LTO sample shows a severe capacity decline at corresponding rate. These results suggest that La modifying is an effective way to improve the chemical stability of the electrode in contact with the electrolyte and improve their cyclability and rate capability during long term cycling. Since high rate performance is an important factor that needs to be considered in fabricating power batteries in industry, the La-modified LTO moves closer to real and large-scale applications. [Copyright &y& Elsevier]

Abstract: This paper reports the preparation of metsulfuron-methyl (MSM) imprinted polymer layer-coated silica nanoparticles toward analysis of trace sulfonylurea herbicides in complicated matrices. To induce the selective occurrence of surface polymerization, the polymerizable double bonds were first grafted at the surface of silica nanoparticles by the silylation. Afterwards, the MSM templates were imprinted into the polymer-coating layer through the interaction with functional monomers. The programmed heating led to the formation of uniform MSM-imprinted polymer layer with controllable thickness, and further improved the reproducibility of rebinding capacity. After removal of templates, recognition sites of MSM were exposed in the polymer layers. As a result, the maximum rebinding capacity was achieved with the use of optimal grafting ratio. There was also evidence indicating that the MSM-imprinted polymer nanoparticles compared with nonimprinted polymer nanoparticles had a higher selectivity and affinity to four structure-like sulfonylurea herbicides. Moreover, using the imprinted particles as dispersive solid-phase extraction (DSPE) materials, the recoveries of four sulfonylurea herbicides determined by high-performance liquid chromatography (HPLC) were 80.2–99.5%, 83.8–102.4%, 77.8–93.3%, and 73.8–110.8% in the spiked soil, rice, soybean, and corn samples, respectively. These results show the possibility that the highly selective separation and enrichment of trace sulfonylurea herbicides from soil and crop samples can be achieved by the molecular imprinting modification at the surface of silica nanoparticles. [ABSTRACT FROM AUTHOR]

[Display omitted] Medicinal plants have been a major resource for drug discovery. Emerging evidence shows that in addition to pharmacologically active components, medicinal plants also contain phytochemical nanomaterials, or phytonanomaterials, which form nanoparticles for drug delivery. In this review, we examine the evidence supporting the existence of phytonanomaterials. Next, we review identification, isolation, and classification of phytonanomaterials, characteristics of phytonanomaterial-derived nanoparticles, and molecular mechanisms of phytonanomaterial assembly. We will then summarize the current progress in exploring phytonanomaterial-derived NPs as therapeutic agents and drug delivery carriers for disease treatment. Last, we will provide perspectives on future discovery and applications of phytonanomaterials. [ABSTRACT FROM AUTHOR]

High-entropy oxides (HEOs) exhibit excellent structural stability, and the synergistic effects among their constituent elements contribute to performance enhancement, providing vast opportunities for designing novel and efficient electrocatalysts. Utilizing four common transition metals such as Fe, Co, Ni, and Cr as the base and introducing a fifth metal, M (M = Mg, Mn, Zn, and Cu), with different outer electron shells, relevant high-entropy oxides with varying sizes were successfully synthesized via the hydrothermal method. Among all considered samples, FCNCMg, with the smallest particle size, possessed a much larger specific surface area, leading to the exposure of more active sites and thus favoring an improvement of the OER performance. The introduction of the fifth metal induced a redistribution of charges among Fe, Co, Ni, and Cr within the catalyst, resulting in different oxidation states for these metals. Mg addition led the XPS peaks of Fe/Ni and Cr/Co elements to shift towards lower and higher binding energies, respectively. This dynamic compensation effect between metal ions synergistically promoted their OER performance. In alkaline environments, FCNCMg exhibited the best OER performance, with an overpotential of 278 mV at 10 mA cm−2 and a Tafel slope of 49.90 mV dec−1. Moreover, it demonstrated excellent stability, achieving 50 h at 10 mA cm−2 and 20 h at 50 mA cm−2. This study, by controlling the composition of HEOs, explored the impact of particle size and synergistic effects on their performance, offering new insights for design and optimization of relevant high-performance HEOs. • A series of spinel (Fe 0.2 Co 0.2 Ni 0.2 Cr 0.2 M 0.2) 3 O 4 materials were successfully synthesized. • The introduction of M (M = Mg, Mn, Zn, and Cu) leads to tunable oxidation states of other elements. • The dynamic compensation effect among metal ions promots the OER activity of the catalysts. • FCNCMg exhibits an overpotential of 278 mV at 10 mA cm−2 and a Tafel slope of 49.90 mV dec−1. • FCNCMg can sustain stably for 50 h at 10 mA cm−2 and 20 h at 50 mA cm−2. [ABSTRACT FROM AUTHOR]

• Branched Ni 3 C nanoparticles in situ grown on the reduced graphene oxide (rGO). • Ni 3 C/rGO composite exhibited a minimum reflection loss of − 42.8 dB. • More interfacial polarization active sites improved reflection loss. Carbide/carbon composites are new types of electromagnetic (EM) wave absorbing materials because of their good stability, light weight, easy synthesis and excellent performance. In this work, monodisperse branched nickel carbide (Ni 3 C) nanoparticles with controlled morphology were fabricated through high-temperature pyrolysis of nickel acetylacetonate under anhydrous and oxygen-free conditions. Then Ni 3 C nanoparticles were uniformly in situ grown on the surface of reduced graphene oxide (rGO) to form nickel carbide/reduced graphene oxide (Ni 3 C/rGO) nanocomposite. Series of characterization and performance tests were conducted, and the results showed that the EM wave absorption performance of Ni 3 C/rGO composite was greatly enhanced compared with that of pure phase Ni 3 C nanoparticles. Due to the combined effects of interfacial polarization loss, conductivity loss and surface defects, Ni 3 C/rGO nanocomposite exhibited strong reflection loss in 2–18 GHz band, which could attenuate the EM waves incident to the internal loss to a greater extent. When the Ni 3 C/rGO composite is at 3.5 mm thickness, the maximum effective absorption bandwidth can reach 3.6 GHz, and at 3.0 mm thickness, the lowest reflection loss value can reach − 42.8 dB. This high-performance nanocomposite can be a new candidate material for EM wave absorption. [ABSTRACT FROM AUTHOR]

Overcoming physiological barrier strategies for treating severe diseases. [Display omitted] Virus-like particles (VLPs) have natural structural antigens similar to those found in viruses, making them valuable in vaccine immunization. Furthermore, VLPs have demonstrated significant potential in drug delivery, and emerged as promising vectors for transporting chemical drug, genetic drug, peptide/protein, and even nanoparticle drug. With virus-like permeability and strong retention, they can effectively target specific organs, tissues or cells, facilitating efficient intracellular drug release. Further modifications allow VLPs to transfer across various physiological barriers, thus acting the purpose of efficient drug delivery and accurate therapy. This article provides an overview of VLPs, covering their structural classifications, deliverable drugs, potential physiological barriers in drug delivery, strategies for overcoming these barriers, and future prospects. [ABSTRACT FROM AUTHOR]

The 3D spherical NiO@MnO 2 composites grown on Ni foam with core-shell structure were prepared by a hydrothermal process followed by a chemical bath deposition process, and then the mechanism improving the electrochemical performance of NiO by MnO 2 modification were investigated by the first-principles calculations for the first time. This core-shell structure promotes an efficient contact between electrolyte and active materials, and the distinct architecture can offer fast transfer channels of ion and electrons. The initial capacitances of NiO, NiO@MnO 2 (deposition time of MnO 2 is 20 min), NiO@MnO 2 (deposition time of MnO 2 is 30 min) and NiO@MnO 2 (deposition time of MnO 2 is 60 min) at 10 A g−1 are 931.6, 1064.4, 1227.2 and 766.8 F g−1, respectively. After 10000 cycles, the reversible capacitances attenuate to 352.8, 661.0, 1089.4 and 616.6 F g−1, respectively. NiO@MnO 2 (deposition time of MnO 2 is 30 min) shows the most excellent reversible capacitance at each cycle and the highest retention rates after 10000 cycles among all samples. The first-principles calculation confirms that a strong interfacial interaction between NiO and MnO 2 can be generated, and then the atomic relaxations at the interface are rather small due to the well-matched interface and epitaxial bonding, resulting in a relatively small interfacial polarization of NiO@MnO 2 composites during cycling. The outstanding rate capability and cycle performance of NiO@MnO 2 (deposition time of MnO 2 is 30 min) electrode are attributed to the synergistic effect and particular 3 D architectures. [ABSTRACT FROM AUTHOR]

NiCo 2 S 4 as a promising anode material for sodium ion batteries (SIBs) with rich redox potential and high theoretical specific capacity, but suffers the poor conductivity and severe volume expansion. The electrode materials with a three-dimensional (3D) framework can facilitate the migration of ions/electrons, enhance structural stability, and alleviate the volume expansion during charging/discharging. Herein, we report the NiCo 2 S 4 nanoparticles anchored on a 3D interpenetrating framework consisting of graphene nanosheets (GNs) and carbon nanotubes (CNTs) to solve the above issues. Benefiting from the structural stability and superior conductivity in special 3D structure, the as-prepared NCS@GNs@CNTs electrode delivers a high initial discharge/charge capacity (558.1/538.8 mAh g1 at 100 mA g−1), superior cyclic stability (362.8 mAh g−1 after 100 cycles at 200 mA g−1) and an excellent rate capability (311.8 mAh g−1 at 5000 mA g−1). Furthermore, the sodium-ion full-cell Na 3 V 2 (PO 4) 3 @C-NCS@GNs@CNTs test demonstrates that NCS@GNs@CNTs exhibits good cycling stability and further illustrates the possibility in practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li-S) batteries appear to be one of the most promising energy-storage devices owing to the unparalleled theoretical specific energy, relatively inexpensive price and abundant resources. Despite these attractive features, the practical performances of sulfur cathode still remain a lot of challenges, such as the electrical insulating nature of S and Li 2 S, huge volume change during cycling, notorious shuttle effect of lithium polysulfide intermediates (LiPSs), sluggish redox kinetics and construction of thick electrodes with high sulfur loading. Here, CoFe 2 O 4 nanoparticles anchored on the carbon nanotube (CNT) paper is proposed as free-standing sulfur host to address the issues. The cross-linking CNT network can serve as conductive matrix and accommodate volume change upon cycling simultaneously. Meanwhile, the CoFe 2 O 4 nanoparticles are capable of effectively anchoring LiPSs to suppress the shuttle effect and accelerating LiPSs conversion to boost redox kinetics. Moreover, the free-standing paper electrode without any binder is conducive to constructing stable cathode with high sulfur loading. In consequence, the well-designed S/CoFe 2 O 4 /CNT paper cathodes deliver impressive electrochemical performance, demonstrating an initial discharge capacity of 755.3 mAh g−1 and remaining a high reversible capacity of 642.6 mAh g−1 after 400 cycles at 2 C with an inconspicuous decay of 0.04% per cycle. The bimetallic oxide CoFe 2 O 4 nanoparticles anchored on the carbon nanotube paper is proposed as free-standing sulfur host with enhanced polysulfide trapping and catalytic effects for advanced Li-S batteries. [Display omitted] • Binder-free host realizes high sulfur loading and energy density for Li-S battery. • CoFe 2 O 4 /CNT paper inhibits the polysulfide shuttling via strong chemical interaction. • CNT-anchored CoFe 2 O 4 catalytically promotes the polysulfide conversion kinetics. • The Li-S battery with S/CoFe 2 O 4 /CNT cathode exhibits enhanced capacity and stability. [ABSTRACT FROM AUTHOR]

We report crosslinker free self assembly of bovine serum albumin (BSA) and a hydrophobic payload paclitaxel (PTX), into nanoparticles by harnessing the temperature driven unfolding of protein. To systematically study the effects of various factors responsible for the key attributes of the nanoparticles, a Resolution IV design was used. 20 formulations were made with pH, temperature, time of heating before and after addition of drug, stirring rate, protein concentration, and protein to drug ratio selected as independent variables. Particle size, encapsulation efficiency, yield and zeta potential were the response variables. Perturbation and Pareto charts were used to single out the important factors, while, mathematical equations and 3D surface charts have been used to describe the relationship between dependent and independent variables. Nanoparticles with size of 188–482 nm were observed with a highly negative zeta potential of −39.5 to −21.9. Nanoparticles obtained had decent encapsulation efficiency (72.5–87.9%) with effective yield (80.0–93.8%). Validation of the mathematical models with 4 runs indicated the good prognostic ability of Resolution IV design. Spectroscopic studies suggested the non-covalent complexation between BSA and PTX as the possible mechanism of self assembly due to irreversible conformational changes in protein. Transmission Electron Microscopy (TEM) revealed spherical nanoparticles with a porous network of PTX–BSA. X-ray Diffraction (XRD) showed amorphous nature of nanoparticles. PTX release from the nanoparticles was found to be controlled release and followed Peppas–Sahlin model. In vitro cytotoxicity of PTX–BSA nanoparticles was comparable to that of Taxol after 48 h treatment. These findings suggest heat driven BSA self assembly as a viable approach to formulate cytotoxic drug carrying nanoparticles which could be efficiently used in anti-cancer therapy. [ABSTRACT FROM AUTHOR]

Modified magnetic starch nanoparticles (FA-StNP@Fe2O3) were synthesized by conjugating folic acid (FA-PEG-NH2) onto the surface of magnetic starch nanoparticles (StNP@Fe2O3) prepared by reverse microemulsion method. The synthesized FA-StNP@Fe2O3 was investigated by transmission electron microscopy and zeta potential analysis. The average size of its well dispersed particles was 250 nm. The iron concentration of 2 mg/g was detected by phenanthroline method. Placing FA-StNP@Fe2O3 nanoparticles in the alternating magnetic field for 30 min resulted in an increase in the suspension temperature from ambient temperature (37°) to a value between 42° and 43°. Co-cultured nanoparticles and Hela cell line or normal HUEC-12 cell line, and the biological effects at the cellular level were investigated in the alternating magnetic field using MTT assay, Hochest-PI double staining and flow cytometry analysis. Experimental results showed that FA-StNP@Fe2O3 within acertain concentration range has no obvious effect on cell proliferation. When treated in the magnetic field, apoptosis rate on Hela induced by FA-StNP@Fe2O3 was 13.4%. Prussian blue staining analysis confirmed that the nanoparticles modified with folic acid had improved ability in tumor cell-targeting, and therefore, potential applications in biomedical and magnetocaloric areas. It is expected be applied in tumor targeting therapy in the near future. [ABSTRACT FROM AUTHOR]

In this work, a novel nano-sized mixed-crystal TiO2 catalyst was obtained under microwave irradiation in hydrogen peroxide solution and its sonocatalytic activity was also investigated through degradation of congo red dye. It was found that the sonocatalytic degradation effect of congo red using nano-sized mixed-crystal TiO2 powder was much higher than that using pure nano-sized rutile phase TiO2 powder. At last, the congo red dyes in aqueous solution were degraded completely and became some simple inorganic ions such as NO, SO and so on. The experiments indicated that the degradation method using such treated nano-sized rutile TiO2 powder as sonocatalyst could be used to treat those non- or low-transparent wastewaters effectively. [ABSTRACT FROM AUTHOR]

We have synthesized Pt@Au and Pt@Cu bimetallic nanoparticles and investigated their surface plasmon resonance (SPR) and plasmon-enhanced photocatalytic activity in the quantum size regime. The SPR wavelength of Pt@Au bimetallic nanoparticles monotonously blue-shifts as the thickness of Pt shell increases comparing with the quantum-sized Au core nanoparticles with diameter dAu = 3.6 ± 0.4 nm. On the other hand, the SPR of Pt@Cu bimetallic nanoparticles blue-shifts at first and then red-shifts as the Pt shell thickness increases comparing to the quantum-sized Cu core nanoparticles with diameter dCu = 3.7 ± 0.5 nm. Then, we comparatively investigated the photocatalytic activities of the Pt@Au nanoparticles with quantum and classical sizes. The photocatalytic rate for 4-NP:NaBH4 is enhanced 2 times by the strong plasmon resonance and the large surface area/volume ratio of quantum-sized Pt@Au nanoparticles. Additionally, the increasing photocatalytic activity of the quantum-sized Pt@Cu with the increase of Pt shell thickness is also observed. These findings reveal the significance of the quantum plasmon resonance on the enhancement of photocatalytic activity. [ABSTRACT FROM AUTHOR]