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Purpose: Joint destruction is a major burden and an unsolved problem in rheumatoid arthritis (RA) patients. We designed an intra-articular mesoporous silica nanosystem (MSN-TP@PDA-GlcN) with anti-inflammatory and joint protection effects. The nanosystem was synthesized by encapsulating triptolide (TP) in mesoporous silica nanoparticles and coating it with pH-sensitive polydopamine (PDA) and glucosamine (GlcN) grafting on the PDA. The nano-drug delivery system with anti-inflammatory and joint protection effects should have good potency against RA., Methods: A template method was used to synthesize mesoporous silica (MSN). MSN-TP@PDA-GlcN was synthesized via MSN loading with TP, coating with PDA and grafting of GlcN on PDA. The drug release behavior was tested. A cellular inflammatory model and a rat RA model were used to evaluate the effects on RA. In vivo imaging and microdialysis (MD) system were used to analyze the sustained release and pharmacokinetics in RA rats., Results: TMSN-TP@PDA-GlcN was stable, had good biocompatibility, and exhibited sustained release of drugs in acidic environments. It had excellent anti-inflammatory effects in vitro and in vivo. It also effectively repaired joint destruction in vivo without causing any tissue toxicity. In vivo imaging and pharmacokinetics experiments showed that the nanosystem prolonged the residence time, lowered the C max value and enhanced the relative bioavailability of TP., Conclusions: These results demonstrated that MSN-TP@PDA-GlcN sustained the release of drugs in inflammatory joints and produced effective anti-inflammatory and joint protection effects on RA. This study provides a new strategy for the treatment of RA., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Chemodynamic therapy (CDT) is an emerging targeted treatment technique for tumors via the generation of highly cytotoxic hydroxyl radical (·OH) governed by tumor microenvironment-assisted Fenton reaction. Despite high effectiveness, it faces limitations like low reaction efficiency and limited endogenous H 2 O 2 , compromising its therapeutic efficacy. This study reports a novel platform with enhanced CDT performance by in situ sono-activated cascade Fenton reaction. A piezoelectric g-C 3 N 4 (Au-Fe-g-C 3 N 4 ) nanosheet is developed via sono-activated synergistic effect/H 2 O 2 self-supply mediated cascade Fenton reaction, realizing in situ ultrasound activated cascade Fenton reaction kinetics by synergistic modulation of electron-hole separation. The nanosheets consist of piezoelectric g-C 3 N 4 nanosheet oxidizing H 2 O to highly reactive H 2 O 2 from the valence band, Fe 3+ /Fe 2+ cycling activated by conduction band to generate ·OH, and Au nanoparticles that lower the bandgap and further adopt electrons to generate more 1 O 2 , resulting in improved CDT and sonodynamic therapy (SDT). Moreover, the Au-Fe-g-C 3 N 4 nanosheet is further modified by the targeted peptide to obtain P-Au-Fe-g-C 3 N 4 , which inhibits tumor growth in vivo effectively by generating reactive oxygen species (ROS). These results demonstrated that the sono-activated modulation translates into a high-efficiency CDT with a synergistic effect using SDT for improved anti-tumor therapy., (© 2023 Wiley-VCH GmbH.)

The drug efflux by P-glycoprotein (P-gp) is the primary contributor of multidrug resistance (MDR), which eventually generates insufficient nuclear drug accumulation and chemotherapy failure. In this paper, reversible covalent nanoassemblies on the basis of catechol-functionalized methoxy poly (ethylene glycol) (mPEG-dop) and phenylboronic acid-modified cholesterol (Chol-PBA) are successfully synthesized for delivery of both doxorubicin (DOX, anti-cancer drug) and tariquidar (TQR, P-glycoprotein inhibitor), which shows efficient nuclear DOX accumulation for overcoming tumor MDR. Through naturally forming phenylboronate linkage in physiological circumstances, Chol-PBA is able to bond with mPEG-dop. The resulting conjugates (PC) could self-assemble into reversible covalent nanoassemblies by dialysis method, and transmission electron microscopy analysis reveals the PC distributes in nano-scaled spherical particles before and after drug encapsulation. Under the assistance of Chol, PC can enter into lysosome of tumor cells via low-density lipoprotein (LDL) receptor-mediated endocytosis. Then the loaded TQR and DOX are released in acidic lysosomal compartments, which inhibit P-gp mediated efflux and elevate nuclear accumulation of DOX, respectively. At last, this drug loaded PC nanoassemblies show significant tumor suppression efficacy in multidrug-resistant tumor models, which suggests great potential for addressing MDR in cancer therapy., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The electrochemiluminescence (ECL) bioassay is prominently carried out with the involvement of the coreactant. To remove the detrimental effects of the coreactant on the ECL of luminophores, herein, a promising ECL immunoassay strategy with biocompatible nanoparticles as the luminophore is proposed, which involves directly and electrochemically oxidizing the luminophore methionine-capped Au (Met@Au) nanocrystals (NCs) without the participation of any coreactant. Met@Au NCs are a kind of n-type nanoparticles, and they can be electrochemically injected with valence band (VB) holes around +0.80 and +1.10 V (vs Ag/AgCl). The electrochemically injected exogenous VB hole can recombine with the endogenous conduction band electron of Met@Au NCs and eventually bring out two coreactant-free and near-infrared ECL processes around 0.80 V (ECL-1) and 1.10 V (ECL-2). The intensity of coreactant-free ECL is primarily determined by the electrochemical oxidation-induced hole-injection process. ECL-2 is considerably stronger than ECL-1 and can be exploited for determining the carcinoembryonic antigen (CEA) in a sandwich immunoassay procedure with a linear range from 0.1 to 50 pg/mL as well as a limit of detection of 0.03 pg/mL (S/N = 3).

Herein, low-triggering-potential (LTP) electrochemiluminescence (ECL) with an onset around 0.0 V (vs Ag/AgCl) is proposed with bovine serum albumin (BSA)-stabilized Au nanocrystals (BSA-AuNCs) as a luminophore and hydrazine hydrate (N 2 H 4 ) as a coreactant. The BSA-AuNCs/N 2 H 4 system can exhibit efficient LTP-ECL around 0.37 V with the luminophore of both monodispersed and surface-confined states. The LTP-ECL of BSA-AuNCs/N 2 H 4 is a kind of single-color emission with a maximum emission wavelength around 740 nm, which is obviously red-shifted for 80 nm from that of BSA-AuNCs PL, and indicates that the ECL is generated in a surface-defect-involved route instead of the band-gap-engineered route. Importantly, BSA-AuNCs can be utilized as ECL tags to perform sandwich-type immunoassays with acceptable sensitivity and selectivity, which exhibits a wide linear response for determining CA125 from 0.5 to 1000 mU/mL and a limit of detection of 0.05 mU/mL (S/N = 3).

The selective accumulation and real-time monitoring of drug release at tumor site are the key bottlenecks to the clinical translation of polyprodrug. Herein, an intracellular self-immolative polyprodrug (PMTO) is exploited, which not only shows the enhanced cellular internalization and selective accumulation in tumor site under the mild hyperthermia triggered by laser irradiation, but also possesses the self-monitoring drug release ability in vivo. The polyprodrug amphiphiles are synthesized by sequential esterification reaction, and hydrophilic poly(ethylene glycol) serves as blocking agent. On account of the mild hyperthermia produced by PMTO under the laser irradiation at tumor site, the cell membranous permeability increases, resulting in the enhanced cellular internalization and drug accumulation in tumor. After internalized by cells, the self-immolative PMTO nanoparticles can release free mitoxantrone (MTO) in intracellular reductive environment, and ratiometric photoacoustic imaging based on distinct signals between MTO and PMTO is presented to trace the drug release in vivo. Finally, this self-monitoring polyprodrug presents significant tumor suppression efficacy, which exhibits great potential for guiding the clinical medication in cancer treatment., (© 2022 Wiley-VCH GmbH.)

The precise treatment of drug-resistant deep bacterial infections remains a huge challenge in clinic. Herein, a polymer-peptide-porphyrin conjugate (PPPC), which can be real-time monitored in infectious site, is developed for accurate and deep sonodynamic therapy (SDT) based on "in vivo self-assembly" strategy. The PPPC contains four moieties, i.e., a hyperbranched polymer backbone, a self-assembled peptide linked with an enzyme-cleavable peptide-poly (ethylene glycol) terminal, a bacterial targeting peptide, and a porphyrin sonosensitizer (MnTCPP) segment. Once PPPC nanoparticles reach the infectious area, the protecting PEG layers are removed due to the over-expressed gelatinase, leading to the secondary assembly into large nanoaggregates and resultant enhanced accumulation of sonosensitizer. The nanoaggregates exhibit enhanced interaction with bacterial membrane and decrease the minimum inhibitory concentration (MIC) significantly. Meanwhile, compared with free MnTCPP, the concentration of which can not be accurately quantified, the accumulation amount of MnTCPP in PPPCs at infectious site can be in situ monitored by magnetic resonance imaging (MRI) using T 1 combined with T 2 . When the concentration of PPPC-1 reaches MIC, the drug-resistant bacterial infection area is exposed to ultrasound irradiation, causing the precise and efficient elimination of bacteria. Therefore, the MRI-guided SDT system shows extraordinary tissue penetration depth, drug concentration monitoring, morphology-transformation induced accumulation and improved treatment capacity toward drug-resistant bacteria., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The shape of a drug delivery system impacts its in vivo behavior such as circulation time, accumulation, and penetration. Considering the advantages of functional dyes in bioapplications, we synthesize a class of nanoaggregates based on BF 2 -azadipyrromethene (aza-BODIPY) dyes, which can realize long blood circulation and deep tumor penetration simultaneously in vivo through morphological transformation modulated by a near-infrared (NIR) laser. First, when the temperature increases, the wormlike nanofibers of the aza-BODIPY-1 aggregate, possessing a long blood circulation time, can be transformed into spherical nanoparticles, which are conducive to increasing the penetration in the solid tumor. Second, without any postmodification, the nanofibers exhibit an outstandingly narrow absorption band in the NIR spectral range, so that they possess ideal photothermal properties. Through 655 nm laser irradiation, the intrinsic photothermal effect causes a local temperature increase to ∼48 °C, realizing the transformation of 1-NFs to 1-NPs. Third, the morphological transformation is real-time detected by photoacoustic (PA) imaging. By monitoring the change of the PA signal at a specific wavelength, the in vivo deformation process of nanomaterials can be traced. Consequently, the in situ morphology transformation of aza-BODIPY-based nanomaterials can simultaneously realize long blood circulation and deep penetration, resulting in the enhanced antitumor outcome.

Mesangial proliferative glomerulonephritis (MsPGN), one of the most common glomerulonephritis pathological types, often leads to end-stage renal disease over a prolonged period. But the current treatment of MsPGN is non-specific and causes serious side effects, thus novel therapeutics and targeting strategies are urgently demanded. By combining the advantages of PEG-PLGA nanoparticles and the size selection mechanism of renal glomerulus, we designed and developed a novel PEG-PLGA nanoparticle delivery system capable of delivering dexamethasone acetate (A-DEX) into glomerular mesangium. We determined that 90 nm was the optimum size to encapsulate A-DEX for glomerular mesangium targeting based on the size-selection mechanism of glomerulus. After intravenous administration in rats, 90 nm DiD-loaded NPs were found to accumulate to a greater extent in the kidney and kidney cortex compared with the free DiD solution. The 90 nm A-DEX NPs are also more stable at room temperature and showed a sustained release pattern. In rat glomerular mesangial cells (HBZY-1) in vitro, we found that the uptake of 90 nm A-DEX NPs was both temperature-dependent and energe-dependent, and they were mostly engulfed via clathrin-dependent endocytosis pathways. In summary, we have successfully developed a glomerular mesangium-targeted PEG-PLGA NPs, which is potential for the treatment of MsPGN.

Nanotherapeutics have encountered some bottleneck problems in cancer therapy, such as poor penetration and inefficient accumulation in tumor site. We herein developed a novel strategy for deep tissue penetration in molecular level and near-infrared (NIR) laser guided in situ self-assembly to solve these challenges. For the proof-of-concept study, we synthesized the polymer-peptide conjugates (PPCs) composed of (i) poly(β-thioester) as thermoresponsive backbone, (ii) functional peptides (cytotoxic peptide and cell-penetrating peptide), and (iii) the NIR molecule with photothermal property. The PPCs in the molecular level with small size (<10 nm) can penetrate deeply into the interior of the tumor at body temperature. Under the irradiation of NIR laser, the temperature rise induced by photothermal molecules led to the intratumoral self-assembly of thermoresponsive PPCs. The resultant spherical nanoparticles can accumulate in tumor and enter cells effectively, inducing cell apoptosis by destroying mitochondria membrane. Through the site-specific size control, a variety of merits of PPCs are realized including deep tumor penetration, enhanced accumulation, and cellular internalization in vivo. Taking advantage of the NIR guided in situ assembly strategy, numerous polymeric or nanoscaled therapeutics with high anticancer activity can be exploited.

Cerebral amyloid β-peptide (Aβ) accumulation resulting from an imbalance between Aβ production and clearance is one of the most important causes in the formation of Alzheimer's disease (AD). In order to preserve the maintenance of Aβ homeostasis and have a notable AD therapy, achieving a method to clear up Aβ plaques becomes an emerging task. Herein, we describe a self-destructive nanosweeper based on multifunctional peptide-polymers that is capable of capturing and clearing Aβ for the effective treatment of AD. The nanosweeper recognize and bind Aβ via co-assembly through hydrogen bonding interactions. The Aβ-loaded nanosweeper enters cells and upregulates autophagy thus promoting the degradation of Aβ. As a result, the nanosweeper decreases the cytotoxicity of Aβ and rescues memory deficits of AD transgenic mice. We believe that this resourceful and synergistic approach has valuable potential as an AD treatment strategy.

In drug delivery systems, pH-sensitive polymers are commonly used as drug carriers, and significant efforts have been devoted to the aspects of controlled delivery and release of drugs. However, few studies address the possible autophagic effects on cells. Here, for the first time, using a fluorescent autophagy-reporting cell line, this study evaluates the autophagy-induced capabilities of four types of pH-sensitive polymeric nanoparticles (NPs) with different physical properties, including size, surface modification, and pH-sensitivity. Based on experimental results, this study concludes that pH-sensitivity is one of the most important factors in autophagy induction. In addition, this study finds that variation of concentration of NPs could cause different autophagic effect, i.e., low concentration of NPs induces autophagy in an mTOR-dependent manner, but high dose of NPs leads to autophagic cell death. Identification of this tunable autophagic effect offers a novel strategy for enhancing therapeutic effect in cancer therapy through modulation of autophagy., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A universal strategy for efficient, mild, and purification-free synthesis and in situ screening of functional polymer-peptide nanomaterials is described. More than 1000 polymer-peptide conjugates (PPCs) with various chemical structures, compositions, and therapeutic efficacy are created. According to this strategy, the structure-function relationship of the PPCs is revealed, and the antitumor efficacies of the top performing PPCs are evaluated in vivo., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The bis(pyrene) conjugated pH-sensitive polymers () were synthesized and self-assembled into nanoparticles through hydrophobic interactions. The Nile red (NR) loaded nanoparticles showed red emission due to the FRET effect. The nanoparticles entered cells via endocytosis, and the microenvironmental pH in the endocytosis process was monitored in situ by the simultaneous dual-wavelength fluorescence changes.

Co-self-assembled vesicular nanoparticles of two structurally comparable amphiphilic boron-dipyrromethene (BODIPY) dyes with dequenchable dual colour fluorescence were prepared for ratiometric imaging of live cells.

A peptide-conjugated poly(β-amino ester) that self-assembles into micelle-like nanoparticles is prepared by a convenient and modular supramolecular approach. The polymer-beclin-1 (P-Bec1) nanoparticles display enhanced cytotoxicity to breast cancer cells through induction of autophagy. This approach overcomes two major limitations of the haploinsufficient tumor suppressor Bec1 compared to small-molecule drugs: poor delivery to tumors owing to enzymatic degradation, and unstable, non-specific bio-distribution and targeting in the tumor tissues., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A series of well-defined thermoresponsive diblock copolymers (PEO45-b-PtNEAn, n=22, 44, 63, 91, 172) were prepared by the atom transfer radical polymerization of trans-N-(2-ethoxy-1,3-dioxan-5-yl) acrylamide (tNEA) using a poly(ethylene oxide) (PEO45) macroinitiator. All copolymers are water-soluble at low temperature, but upon quickly heating to 37 °C, laser light scattering (LLS) and transmission electron microscopy (TEM) characterizations indicate that these copolymers self-assemble into aggregates with different morphologies depending on the chain length of PtNEA and the polymer concentration; the morphologies gradually evolved from spherical solid nanoparticles to a polymersome as the degree of polymerization ("n") of PtNEA block increased from 22 to 172, with the formation of clusters with rod-like structure at the intermediate PtNEA length. Both the spherical nanoparticle and the polymersome are stable at physiological pH but susceptible to the mildly acidic medium. Acid-triggered hydrolysis behaviors of the aggregates were investigated by LLS, Nile red fluorescence, TEM, and (1)H NMR spectroscopy. The results revealed that the spherical nanoparticles formed from PEO45-b-PtNEA44 dissociated faster than the polymersomes of PEO45-b-PtNEA172, and both aggregates showed an enhanced hydrolysis under acidic conditions. Both the spherical nanoparticle and polymersome are able to efficiently load the hydrophobic doxorubicin (DOX), and water-soluble fluorescein isothiocyanate-lysozyme (FITC-Lys) can be conveniently encapsulated into the polymersome without using any organic solvent. Moreover, FITC-Lys and DOX could be coloaded in the polymersome. The drugs loaded either in the polymersome or in the spherical nanoparticle could be released by acid triggering. Finally, the DOX-loaded assemblies display concentration-dependent cytotoxicity to HepG2 cells, while the copolymers themselves are nontoxic.

Microstructural evolution and strengthening mechanisms of Mg-3Sn-1Ca based alloys with additions of different amounts of AlN nano-particles were investigated. It was found that with increasing the amount of AlN nano-particles the grain size decreases obviously. The existence of AlN nano-particles could refine the primary crystal phases CaMgSn, which provided more heterogeneous nucleation sites for the formation of magnesium. Moreover, such nano-particles could also restrict the grain growth during solidification. After adding AlN nano-particles, both the tensile properties at room temperature and high temperature 250 °C and the hardness are largely improved. The improvement of strength is attributed to grain refinement and second phase refinement. [ABSTRACT FROM AUTHOR]

Abstract: Double-cantilever-beam tests were applied to investigate the mode I interlaminar fracture toughness of carbon fibre/epoxy laminates, in which the epoxy matrices were incorporated with rubber and silica nano-particles, either singly or jointly. It is shown that the toughness is improved owing to the presence of these nano-particles although nano-rubber is more effective than nano-silica. Further, by keeping the total particle weight percentage constant in epoxies (e.g., at 8 and 12wt.%) filled with equal amount of nano-silica and nano-rubber, the interlaminar toughness values of the hybrid laminates are always higher than those with nano-silica filled epoxies but lower than those with nano-rubber filled matrices. Scanning electron microscopy examination of the delaminated surfaces of composite laminates filled with nano-particles revealed that cavitation of nano-rubber particles/void growth and debonding of nano-silica from epoxy matrix are responsible for the improved interlaminar toughness observed. It is also shown that the bulk toughness of nano-particle filled epoxies cannot be fully transferred to the interlaminar toughness of composite laminates, being limited by the constraint effect imposed by the carbon fibres. Finally, the role of fibre-bridging on the delaminated crack and hence delamination toughness is discussed. [Copyright &y& Elsevier]

In this study, we explored the influence of two metal oxide nanoparticles, nano CuO and nano ZnO (10, 50, 250 mg/kg), on accumulation of bifenthrin (100 μg/kg) in earthworms (Eisenia fetida) and its mechanism. The concentrations of bifenthrin in earthworms from binary exposure groups (bifenthrin + CuO and bifenthrin + ZnO) reached up to 23.2 and 28.9 μg/g, which were 2.65 and 3.32 times of that in bifenthrin exposure group without nanoparticles, respectively, indicating that nanoparticles facilitated the uptake of bifenthrin in earthworms. The contents of biomarkers (ROS, SOD, and MDA) in earthworms indicated that nanoparticles and bifenthrin caused damage to earthworms. Ex vivo test was utilized to investigate the toxic effects of the pollutants to cell membrane of earthworm coelomocytes and mechanism of increased bifenthrin accumulation. In ex vivo test, cell viability in binary exposure groups declined up to 30% and 21% compared to the control group after 24 h incubation, suggesting that coelomocyte membrane was injured by the pollutants. We conclude that nanoparticles damage the body cavity of earthworms, and thus lead to more accumulation of bifenthrin in earthworms. Our findings provide insights into the interactive accumulation and toxicity of nanoparticles and pesticides to soil organisms. Image 1 • Nanoparticles enhanced the bifenthrin accumulation in the earthworms. • Damaged body cavity caused by nanoparticles increases the accumulation of bifenthrin. • Higher toxicity caused by nano CuO results in larger Sorbefacient Coefficient value. • Nano CuO leads to severer damage to individual earthworms compared to nano ZnO. [ABSTRACT FROM AUTHOR]

Bulk nanostructured (NS) aluminum alloys typically have high strength but with extremely limited ductility. An advanced two-step thermomechanical processing, i.e. semisolid isothermal treatment coupled with equal-channel angular pressing (ECAP), was adopted to achieve high strength (413±2.5 MPa) and high elongation (12.0±0.6 %) in bulk NS Al-4.5 wt%Cu binary alloy. The broken nanoscale Al 2 Cu particles (∼50–80 nm) from lamellar eutectic, dynamic precipitations Al 2 Cu (∼30–60 nm), refined grains, and high-density dislocations are believed to be key contributors for the high strength. The bimodal grain structure, which caused a well-balanced work hardening and a good deformation compatibility, is critical for the enhanced strength-ductility synergy. This work demonstrates a new approach for improving strength-ductility synergy in interdendritic-eutectic type aluminum alloys. • Al 2 Cu nano-lamellae eutectic was prepared by quenching after semi-solid isothermal treatment. • Two types of nanoparticles were obtained in Al-4.5Cu binary alloy, i.e. precipitated nanoparticles and broken nanoparticles. • A good synergistic effect of high strength (UTS: 413 MPa) and high ductility (12 %) has been achieved in Al-Cu binary alloy. • The nanoparticles and high-density dislocations promote strength, and the bimodal grain structure achieves good plasticity. [ABSTRACT FROM AUTHOR]

Aluminum alloy is widely used in high˗speed train bodies. However, compared with the base material, the tensile strength and elongation of its laser welded joints are significantly reduced, which limits the lightweight application of the next generation of high˗speed trains. The research in this article indicates that laser welding with Ca micro˗alloyed 5356 filler metal has changed the mechanical properties and microstructure of the weld seam. Without the Ca in the filler metal, the strength and elongation of the laser welded joint are only 215.5 MPa and 3.1 %. When the Ca content in the filler metal reaches 0.04 wt%, the laser welded joint has high tensile strength and maximum elongation, which are 251.5 MPa and 9.7 %, respectively. As the Ca content increases, the grain size of the welded joint gradually decreases, and the limiting effect of Ca element on the growth of α˗Al grains is the main reason for grain refinement. In addition, the addition of Ca transforms the coarse Fe˗rich phase in the weld into a fine˗grained second phase, while promoting the formation of deformable nanoparticles γ˗Al 12 Mg 17 , leading to the accumulation of dislocations and successfully improving the strength and plasticity of laser welded joints. When the Ca content further increases, the second phase grows, and the tensile strength and plasticity of the joint slightly decrease, but are still higher than that of the joint without Ca. [ABSTRACT FROM AUTHOR]

• 3D flower-like Au@N-Bi 2 O 2 CO 3 /g-C 3 N 4 heterojunction was successfully designed. • The strong SPR effect of Au obviously enhanced the light response ability. • Au loading significantly boosted separation rate of photogenerated carriers. • 2 %Au@NBOC/CN presented highest photocatalytic activity for SIBX and p-cresol. In this work, 3D flower-like Au@N-Bi 2 O 2 CO 3 /g-C 3 N 4 heterojunction was successfully prepared by deposition method. The loading content of Au was regulated to enhance the light absorption performance and accelerate the separation of photogenerated carriers. The crystal structure and microstructure of the photocatalyst were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The activity of heterojunction photocatalysts was investigated by the degradation of sodium isobutyl xanthate (SIBX) and p-cresol under the simulated sunlight. The results show that the 2 %Au@N-Bi 2 O 2 CO 3 /g-C 3 N 4 heterojunction exhibits the highest photocatalytic activity for the degradation of SIBX and p-cresol, which was 3.6 and 3.7 times of that of the pristine N-Bi 2 O 2 CO 3 /g-C 3 N 4 , respectively. This work provides useful guidance for the construction of heterojunctions with excellent photocatalytic properties. [ABSTRACT FROM AUTHOR]

A novel Mg-8Gd-2Y-1.5Zn-1Mn (GYZ-1Mn, wt.%) alloy with extraordinary high-temperature mechanical properties was developed by introducing RE/Zn segregation on α-Mn nanoparticles. Its ultimate tensile stress (UTS) and yield stress (YS) are 312 MPa and 248 MPa at 300 ℃, which are 87 MPa and 52 MPa higher than the highest strengths of other Mg-Gd-Y-Zn alloys reported in the previous literature. The outstanding performance of GYZ-1Mn alloy was associated with the segregation of RE/Zn atoms on the α-Mn nanoparticles, which facilitated the formation of fine lamellar long period stacking ordered (LPSO) phase and impeded the coarsening of α-Mn. Consequently, retarded dynamic recrystallization behavior occurred in the GYZ-1Mn, resulting in fine grain size, high density of geometrically necessary dislocations and strong fiber texture intensity to strengthen the high-temperature mechanical properties. Hence, this work paved a novel path for the development of heat-resistant Mg alloys by introducing elemental segregation on nanoparticles. [Display omitted] [ABSTRACT FROM AUTHOR]

Thiol-reactive group - pyridyl disulfide functionalized magnetic nanoparticles were prepared via co-precipitation following functionalization by stöber method. The particles were characterized and employed to fast and selective conjugate and isolate protein with free thiol from mixed proteins under mild condition. And the released protein has the original sulfhydryl group without any unnecessary modification. [ABSTRACT FROM AUTHOR]

Immunotherapy has shown promising treatment effects for a variety of cancers. However, the immune treatment efficiency for solid tumors is limited owing to insufficient infiltration of immune cells into solid tumors. The conversion of tumor-supportive macrophages to tumor-suppressive macrophages, inducing the functional reversal of macrophages, is an effective method and contributes to a subsequent antitumor response. The current challenge in the field is the poor distribution and systemic side effects associated with the use of cytokines. As a solution to this issue, we designed and synthesized microenvironment-responsive nanoparticles (P) with IL-12 payload (IL-12⊂P1). These nanoparticles could promote the systemic administration and release of IL-12 in the tumor microenvironment, and the locally responsive property of IL-12⊂P1 could subsequently re-educate tumor-associated macrophages (TAMs). In particular, our results illustrated the great therapeutic effects derived from the functional conversion of macrophages. Our strategy was to design a microenvironment-responsive material for local macrophage modification to overcome the physiological barrier of solid tumors. The shifting of macrophage phenotypes via IL-12⊂P1 achieved immunomodulation in the microenvironment for cancer therapy, with negligible cytotoxicity. We expect that the functional regulation of TAMs by pH-responsive nanomaterials is a promising therapeutic approach for cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Abstract: A systematic study on the effects of silica and rubber nano-particles on the fracture toughness behavior of epoxy was conducted. Mode I fracture toughness (GIC ) of binary silica/epoxy, binary rubber/epoxy and ternary silica/rubber/epoxy nanocomposites with different particle weight fractions was obtained by compact tension tests. It is found that GIC of epoxy can be significantly increased by incorporating either rubber or silica nano-particles. However, hybrid nanocomposites do not display any “synergistic” effect on toughness. Microstructures before and after fracture testing were examined to understand the role of nano-particles on the toughening mechanisms. [Copyright &y& Elsevier]