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The clinical success of radiotherapy is greatly hampered due to its intolerable off-target cytotoxicity induced by the high dose of radiation. Meanwhile, low dose of irradiation greatly potentiates the intratumoral angiogenesis, which promotes the local relapse and metastasis of tumor. Therefore, it is essential to reduce the irradiation dosage while inhibiting the tumor angiogenesis during radiotherapy. In this work, tumor vessel specific ultrafine Au@I nanoparticles (AIRA NPs) are fabricated and used as targeted radiosensitizers. Due to the presence of Au and iodine, these AIRA NPs exhibit superb X-ray attenuation for contrast-enhanced computed tomography (CT). Once injected, these AIRA NPs bind specifically to both newly formed tumor vessels in peri- and intratumoral regions and pre-existing tumor vessels. Upon radiation under CT guidance, AIRA NPs remarkably enhanced the killing efficacy against tumors in vivo with respect to radiation alone or anti-angiogenesis chemotherapy. Meanwhile, down-regulation of the level of circulating VEGF cytokine further indicates that our strategy can eradicate tumor without risking the recurrence of hypoxia and angiogenesis. Our demonstration provides a robust method of cancer therapy integrating good biocompatibility, high specificity and relapse-free manner alternative to traditional metal NPs enhanced radiotherapy. [ABSTRACT FROM AUTHOR]

Calreticulin (CRT) on the cell surface that acts as an "eat me" signal is vital for macrophage-mediated programmed cell removal. The polyhydroxylated fullerenol nanoparticle (FNP) has appeared as an effective inducer to cause CRT exposure on cancer cell surface, but it failed in treating some cancer cells such as MCF-7 cells based on previous findings. Here, we carried out the 3D culture of MCF-7 cells, and interestingly found that the FNP induced CRT exposure on cells in 3D spheres via re-distributing CRT from endoplasmic reticulum (ER) to cell surface. Phagocytosis experiments in vitro and in vivo illustrated the combination of FNP and anti-CD47 monoclonal antibody (mAb) further enhanced macrophage-mediated phagocytosis to cancer cells. The maximal phagocytic index in vivo was about three times higher than that of the control group. Moreover, in vivo tumorigenesis experiments in mice proved that FNP could regulate the progress of MCF-7 cancer stem-like cells (CSCs). These findings expand the application of FNP in tumor therapy of anti-CD47 mAb and 3D culture can be used as a screening tool for nanomedicine. [Display omitted] • Fullerenol nanoparticle (FNP) reduces the toxicity of anti-CD47 antibodies therapy. • 3D culture enhances the sensitivity of MCF-7 cells to FNP. • FNP inhibits the progression of MCF-7 cancer stem cells. [ABSTRACT FROM AUTHOR]

Cobalt oxide (Co 3 O 4 )-based materials have been extensively investigated as efficient electrocatalysts for non-enzymatic glucose biosensing. The proper tuning the structure of Co 3 O 4 -based materials could improve sensing performances for glucose detection. Herein, we have developed a combined self-assembly and calcination method to prepare nanoparticles-assembled Co 3 O 4 nanosheets, which exhibit good sensing performances for glucose biosensing. The Co 3 O 4 nanosheets were prepared by the following three steps: (i) the Co 2+ modified graphene oxide (GO) was prepared by the self-assembly of Co 2+ and GO in aqueous solution firstly, and then Co 2+ modified GO film was obtained by vacuum filtration method; (ii) after calcination of Co 2+ modified GO film in N 2 atmosphere, Co 3 O 4 nanoparticles modified reduced GO (RGO) was obtained; (iii) finally, nanoparticles-assembled Co 3 O 4 nanosheets were obtained by calcination of Co 3 O 4 modified RGO in air to remove RGO template. Most importantly, Co 3 O 4 nanosheets exhibit good electrocatalytic activity for oxidation of glucose, leading to high-performance glucose sensor. The detection limit and linear range of Co 3 O 4 nanosheets-based glucose sensor in the present work are 0.15 μM, and 1–50 μM, respectively. Furthermore, such sensor also shows excellent selectivity for glucose detection, compared to the commonly interfering species including dopamine, and uric acid. [ABSTRACT FROM AUTHOR]

Nanoparticles-assembled NiO nanosheets have been successfully prepared using graphene oxide (GO) film as template, where the Ni 2+ ion was firstly adsorbed in GO film, followed by calcination in N 2 to form NiO-based materials and calcination in air to remove carbon-based template. The morphology, structure, and electrochemical activities of these NiO nanosheets were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and electrochemical techniques, respectively. It is found that the NiO nanosheets thus obtained could electrochemically catalyze glucose oxidation in 0.1 M NaOH, leading to fabrication of non-enzymatic glucose sensor. The glucose sensor based on NiO nanosheets exhibits detection limit of 0.18 μM, and linear range from 1 μM to 0.4 mM with the sensitivity of 1138 μA mM −2 cm −2 . Furthermore, such glucose sensor also shows excellent selectivity for detection of glucose, compared to the commonly interfering species, such as ascorbic acid, dopamine, and uric acid. [ABSTRACT FROM AUTHOR]

The development of graphene-based room temperature gas sensors has drawn massive attention due to their unique advantage of gas sensing at room temperature. In this paper, in pursuit of developing high-performance graphene-based gas sensors, a NO 2 gas sensor has been successfully fabricated using sulfonated reduced graphene oxide (S-rGO) anchoring with SnO 2 nanoparticles as sensing materials. The SnO 2 nanoparticles modified S-rGO (SnO 2 /S-rGO) hybrids were prepared by deposition of SnO 2 nanoparticles on the surface of S-rGO through hydrothermal synthesis method. The combined characterizations of X-ray diffraction, UV–vis spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, energy-dispersive spectroscopy, as well as N 2 sorption isotherm indicate the successful preparation of SnO 2 /S-rGO hybrids with porous structure. Most importantly, SnO 2 /S-rGO hybrids exhibit good sensing performances for detection of NO 2 at room temperature, such as high response, fast response and recovery rate, and good selectivity. The sensor based on SnO 2 /S-rGO hybrids exhibits better sensing performances than the previously reported rGO-based gas sensors. Furthermore, the excellent sensing performances of sensor based on SnO 2 /S-rGO also render it suitable for development of high performance gas sensors operated at room temperature. [ABSTRACT FROM AUTHOR]

By pyrolyzed the products from hydrothermal reaction of 1, 4, 5, 8‐naphthalene tetramethyl anhydride, NaOH and FeSO4, the nanoparticles of FeFe2O4 were produced, and then its electrochemical performance of oxygen reduction reaction (ORR) was evaluated in O2 saturated 0.1 M KOH solution. The results indicated that, among all the as‐prepared samples, FeFe2O4‐0.50 was mainly composed of uniformly dispersed spherical nanoparticles of 20‐30nm and behaved the best ORR catalytic performance. Its half‐wave potential and limiting diffusion current density was 0.61 V and −1.85 mA cm−2@0.4 V vs. RHE), respectively, higher about 20 mV and 1.29 mA cm−2 than that of FeFe2O4 (0.59 V and −0.56 mA cm−2@0.4 V vs. RHE). In addition, FeFe2O4‐0.50 also showed stronger stability as well as methanol/CO tolerance than that of commercial 20 % Pt/C. It was the evenly dispersed FeFe2O4 nanoscale and Fe−O bond in FeFe2O4‐0.50 that contributed its excellent electrochemical performance and tolerance for CO and methanol. The as‐prepare FeFe2O4‐0.50 might be a potential alternative catalyst for ORR in fuel cell. [ABSTRACT FROM AUTHOR]

To achieve a drug delivery system combining the programmable long circulation and targeting ability, surface engineering nanoparticles (NPs), having a sandwich structure consisting of a long circulating outmost layer, a targeting middle layer and a hydrophobic innermost core were constructed by mixing a matrix metalloproteinase MMP2 and MMP9-sensitive copolymers (mPEG-Pep-PCL) and folate receptor targeted copolymers (FA–PEG–PCL). Their physiochemical traits including morphology, particle size, drug loading content, and in vitro release profiles were studied. In vitro studies validated that the inhibition efficiency of tumor cells was effectively correlated with NP concentrations. Furthermore, The PEG layer would detach from the NPs due to the up-regulated extracellular MMP2 and MMP9 in tumors, resulting in the exposure of folate to enhance the cellular internalization via folate receptor mediated endocytosis, which accelerated the release rate of CPT in vivo . The antitumor efficacy, tumor targeting ability and bio-distribution of the NPs were examined in a B16 melanoma cells xenograft mouse model. These NPs showed improved tumor target ability and enhanced aggregation of camptothecin (CPT) in tumor site and prominent suppression of tumor growth. Thus this mPEG-Pep-PCL@FA–PEG–PCL core–shell structure NP could be a better candidate for the tumor specific delivery of hydrophobic drug. [ABSTRACT FROM AUTHOR]

• Co-Salen complexes containing different groups and bearing potassium iodide (KI) complexed with crown ether (K@SCs) were prepared. • Salen derivative organic polymer as heterogeneous catalyst for CO 2 cycloaddition reaction. • Alkali metal halides and Lewis acids have good synergistic effects in catalytic reactions. Metallosalen presents very important applications in both homogenous and heterogeneous catalysis. Correspondingly, porous polymeric metallosalen combined with the performance of organometallics and heterogeneous polymers possess potential in CO 2 fixation reactions. Herein, a family collection of K@SCs were conceived and obtained by combining cobalt-salen complexes with different groups and diaminobenzene-18-crown-6 complexed with KI, which allows multiphase catalytic immobilization of CO 2 to epoxides. Catalyst K@SC-3 can fix CO 2 into a variety of substituted epoxides in >90% yields to the corresponding cyclic carbonates in co-catalyst-free and solvent-free conditions. Furthermore, K@SC-3 can be recovered and reused at least six times by simple centrifugal separation, demonstrating superior stability. The kinetics experiments were also carried out at varied temperatures catalyzed by K@SC-3. It is concluded that a first-order equation of epoxide was proved and the activation energy was calculated to be 27.13 KJ/mol. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, SnO 2 nanoparticles (NPs) decorated reduced graphene oxide hybrids with abundant vacancies (designated as SnO 2 -RGO-OVs) have been successfully prepared by a combined hydrothermal synthesis and chemical solution deposition method. It is found that high density SnO 2 NPs with the size of 3–5 nm are uniformly distributed on the surface of RGO nanosheets. Most importantly, SnO 2 -RGO-OVs hybrids exhibit excellent room-temperature NO 2 sensing properties with the low detection limit of 50 ppb. When SnO 2 -RGO-OVs-based sensor was exposed to 1 ppm NO 2 , the response is 3.80 and response time and recovery time are 14 s and 190 s, respectively. These sensing performances are superior to those of most reported room-temperature NO 2 sensors based on RGO-based materials and other materials. The excellent sensing performances of SnO 2 -RGO-OVs hybrids can be attributed to their specific structure, e.g., RGO that could facilitate transferring carriers during sensing progress, and abundant OVs that could facilitate adsorption of more NO 2 molecules onto SnO 2 NPs in SnO 2 -RGO-OVs hybrids. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Pd-SR-V O is fabricated by Pd nanoparticles and oxygen vacancy to modulate SnO 2 modified RGO. • Impressively, the response value of Pd-SR-V O for 1 ppm NO 2 at room temperature reaches to 9.8. • Notably, the response even could reach to 3.0 in 100 ppb NO 2 at room temperature. • The improvement of sensitivity is attributed to the synergy of Pd NPs and oxygen vacancies. Reduced graphene oxides (RGO)-based materials exhibit high carrier mobility and selective recognition ability to NO 2 , making them constitute promising platform for room-temperature NO 2 detection. However, the low sensitivity becomes the main bottleneck for their further development. Here, we demonstrate that synergy of Pd nanoparticles (NPs) and oxygen vacancies can modulate the surface active sites over SnO 2 NPs modified RGO hybrids (labeled as SR), leading to improving the sensitivity of room-temperature NO 2 sensors. Experimentally, a wet-chemical method was used to introduce oxygen vacancies onto SR, leading to forming SR with rich oxygen vacancies (labeled as SR-Vo), which were subsequently deposited with Pd NPs, resulting in preparing Pd NPs loaded SR-Vo hybrids (labeled as Pd-SR-Vo). Impressively, the response value to 1 ppm NO 2 of Pd-SR-Vo hybrids reaches to 9.8, which is much higher than that of R-Vo hybrids (5.6) and SR hybrids (3.3). The improvement of sensitivity toward NO 2 for Pd-SR-Vo hybrids is attributed to the synergy effect of Pd NPs and oxygen vacancies, including shortening the band gap of Pd-SR-Vo hybrids with raising conduction band level, widening the width of electron depletion layer between SnO 2 -Vo and RGO, introducing Schottky contact between Pd and SnO 2 -Vo, improving efficiency for gas sensing reaction. This work not only provides an efficient approach to fabricate high-performance NO 2 sensors, but also opens a new avenue for sensing materials design and modification. [ABSTRACT FROM AUTHOR]

In this work, we have reported a novel NO 2 sensor using molybdenum disulfide nanoparticles (MoS 2 NPs) decorated RGO (MoS 2 -RGO) hybrids as sensing materials, where MoS 2 -RGO hybrids were prepared by a two-step wet-chemical method. Firstly, MoS 2 NPs prepared by modified liquid exfoliation method from bulky MoS 2 powder. Then, MoS 2 -RGO hybrids were obtained by self-assembly of MoS 2 NPs and GO nanosheets, followed by a facile hydrothermal treatment progress. The combined characterizations indicate that MoS 2 NPs with the size of 3–5 nm are uniformly dispersed on RGO nanosheets. Most importantly, the sensor based on MoS 2 -RGO hybrids could detect NO 2 at room temperature. To further improve sensing performances, especially response and recovery rate, sensing properties are further examined by increasing the operation temperature to 160 °C. It is notably seen that MoS 2 -RGO-based NO 2 sensor not only shows improved sensitivity to NO 2 compared to pure RGO-based sensor, but also exhibits fast response and recovery characteristics (response time and recovery time are 8 s and 20 s toward 3 ppm NO 2 ). This work paves a new way for application of MoS 2 and RGO in chemical sensors, providing an effective method for fabrication of NO 2 sensors with high sensitivity and fast response/recovery rate. [ABSTRACT FROM AUTHOR]

Osteogenic and antibacterial activities are two basic requirements for orthopedic implants. The present study mainly focused on the investigation of the osteoblast behaviors and antibacterial activities of Sr/Ag-incorporated titanium dioxide (TiO 2) nanotube array (TNT) on the titanium surface. To this end, the Sr-incorporated TNT was firstly fabricated on the titanium surface by electrochemical anodization and hydrothermal treatment, and then Ag nanoparticles (AgNPs) were incorporated onto the nanotubes by reduction of the adsorbed Ag+ through ultraviolet (UV) irradiation. The TiO 2 nanotubes had excellent hydrophilicity and Sr incorporation can further enhance the hydrophilicity; however, the AgNPs loading could slightly increase water contact angle. The release of Sr2+ can not only promote osteoblast adhesion, proliferation and mineralization, but also up-regulate the alkaline phosphatase (ALP) and osteocalcin (OCN) expression. The introduction of AgNPs on Sr-incorporated nanotubes did not significantly influence the osteoblast cell behaviors; however, it can effectively inhibit the adhesion and growth of Escherichia coli. Therefore, the method of the present study is expected to be suitable for surface modification of titanium surface to simultaneously enhance the osteo-bonding ability and antibacterial activities for bone repair. Unlabelled Image • The Sr ions and Ag nanoparticles were incorporated into titanium oxide nanotubes. • The Sr/Ag-incorporated nanotubes displayed excellent hydrophilicity. • The released Sr2+ from nanotubes can significantly enhance osteoblast growth. • The Ag+ from nanotubes endow the nanotubes with better antibacterial activity. [ABSTRACT FROM AUTHOR]