Search

As a natural polyphenol, curcumin (Cur) has exhibited a range of bioactive properties, including anti-inflammatory, anti-oxidant, and anti-infection properties. However, the chemical instability and low water solubility of Cur hinder its wide application. Herein, Cur-loaded chitosan/lecithin nanoparticles (CCL NPs) were prepared by the electrostatic self-assembly method. The prepared CCL NPs showed a small particle size (122.86 ± 1.53 nm) with homogeneous distribution (PDI = 0.17 ± 0.01). The high EE (79.34 ± 2.93 %) and LC (9.33 ± 0.34 %) indicated that most of Cur was encapsulated in CCL NPs. Meanwhile, the Cur was released from CCL NPs in a quick and sustained way after being exposed to simulated gastrointestinal fluids. The CCL NPs displayed superior anti-oxidant activity than that of free Cur. Moreover, the in vivo pharmacokinetic studies showed that the CCL NPs could lead to a ~ 2.64-fold increase in oral bioavailability compared with that of free Cur. All these findings indicated that the formation of CCL NPs would be a promising platform to deliver Cur in the food industry., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The wide application of ovine oocyte vitrification is limited by its relatively low efficiency. Nanoparticle is potentially to be used in cryopreservation technology for its unique characteristics with high biocompatibility, potent antioxidant property as well as superiority in membrane permeation and heat transduction. However, the effect of nanoparticle on ovine oocyte cryopreservation as well as the underlying mechanism has not been systematically evaluated. The objective of this study was to investigate the impact of nanoparticles on ovine oocytes cryopreservation and further identify the underlying mechanism. Firstly, the effects of Hydroxyapatite (HA) and Fe 3 O 4 nanoparticles on the developmental potential of vitrified ovine oocytes were determined, and the results showed that neither HA (VC = 85.95 ± 6.23 % vs. VH = 92.47 ± 8.11 %, P > 0.05) nor Fe 3 O 4 (VC = 85.95 ± 6.23 % vs. VF = 89.39 ± 6.32 %, P > 0.05) had adverse effect on the survival rate of vitrified-thawed oocytes. Notably, both HA (VC = 77.78 ± 0.09 % vs. VH = 44.00 ± 0.09 %, P＜0.01) and Fe 3 O 4 (VC = 77.78 ± 0.09 % vs. VF = 51.67 ± 0.15 %, P＜0.01) nanoparticles effectively reduced the level of oocyte apoptosis after freezing and thawing. What's more, HA could significantly improve the cleavage rate of frozen oocytes (VC = 33.79 ± 2.83 % vs. VH = 59.54 ± 4.13 %, P＜0.05). Moreover, reduced reactive oxygen species (ROS) level (VC = 13.66 ± 0.47 vs. VH = 12.61 ± 0.53, P < 0.05), increased glutathione (GSH) content (VC = 60.69 ± 7.89 vs. VH = 87.92 ± 1.05, P < 0.05) and elevated mitochondrial membrane potential (MMP) level (VC = 1.43 ± 0.04 vs. VH = 1.63 ± 0.01，P＜0.01) were observed in oocytes treated with HA nanoparticles when compared with that of the control group. Furthermore, Smart-RNA sequence technology was utilized to identify differentially expressed mRNAs (DEMs) induced by nanoparticles during cryopreservation. When compared with the control counterparts, a total of 721 DEMs (309 up-regulated and 412 down-regulated mRNAs) were identified in oocytes treated with HA, while 702 DEMs (480 up-regulated and 222 down-regulated mRNAs) were identified in oocytes treated with Fe 3 O 4 . A comparison of DEMs showed that total 692 mRNAs were expressed in oocytes treated with HA and Fe 3 O 4 . Notably, we discovered that 15 mRNAs were specially highly expressed in oocytes treated with HA, and Focal adhesion signaling pathway mainly contributed to the improved ovine oocyte quality after vitrification by alleviating oxidative stress., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Photothermal therapy (PTT), particularly in the near-infrared-II (NIR-II) range, has attracted widespread attention over the past years. However, the accompanied inflammatory responses can result in undesirable side effects and contribute to treatment ineffectiveness. Herein, we introduced a novel biodegradable nanoplatform (CuS/HMON-PEG) capable of PTT and hydrogen sulfide (H 2 S) generation, aimed at modulating inflammation for improved cancer treatment outcomes. The embedded ultrasmall copper sulphide (CuS) nanodots (1-2 nm) possessed favorable photoacoustic imaging (PAI) and NIR-II photothermal capabilities, rendering CuS/HMON-PEG an ideal phototheranostic agent. Upon internalization by 4T1 cancer cells, the hollow mesoporous organosilica nanoparticle (HMON) component could react with the overproduced glutathione (GSH) to produce H 2 S. In addition to the anticipated photothermal tumor ablation and H 2 S-induced mitochondrial dysfunction, the anti-inflammatory regulation was also been demonstrated by the downregulation of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1beta (IL-1β). More importantly, the modulation of inflammation also promoted wound healing mediated by PTT. This work not only presents a H 2 S-based nanomodulator to boost NIR-II PTT but also provides insights into the construction of novel organic/inorganic hybrid nanosystems., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

microRNAs (miRNAs) are small, non-coding RNAs that regulate expression of multiple genes. MiR-193a-3p functions as a tumor suppressor in many cancer types, but its effect on inducing specific anti-tumor immune responses is unclear. Therefore, we examined the effect of our lipid nanoparticle (LNP) formulated, chemically modified, synthetic miR-193a-3p mimic (INT-1B3) on anti-tumor immunity. INT-1B3 inhibited distant tumor metastasis and significantly prolonged survival. INT-1B3-treated animals were fully protected against challenge with autologous tumor cells even in absence of treatment indicating long-term immunization. Protection against autologous tumor cell challenge was hampered upon T cell depletion and adoptive T cell transfer abrogated tumor growth. Transfection of tumor cells with our miR-193a-3p mimic (1B3) resulted in tumor cell death and apoptosis accompanied by increased expression of DAMPs. Co-culture of 1B3-transfected tumor cells and immature DC led to DC maturation and these mature DC were able to stimulate production of type 1 cytokines by CD4+ and CD8+ T cells. CD4-CD8- T cells also produced type 1 cytokines, even in response to 1B3-transfected tumor cells directly. Live cell imaging demonstrated PBMC-mediated cytotoxicity against 1B3-transfected tumor cells. These data demonstrate for the first time that miR-193a-3p induces long-term immunity against tumor development via modulation of the tumor microenvironment and induction of immunogenic cell death.

The ferroptosis pathway is recognized as an essential strategy for tumor treatment. However, killing tumor cells in deep tumor regions with ferroptosis agents is still challenging because of distinct size requirements for intratumoral accumulation and deep tumor penetration. Herein, intelligent nanocapsules with size-switchable capability that responds to acid/hyperthermia stimulation to achieve deep tumor ferroptosis are developed. These nanocapsules are constructed using poly(lactic-co-glycolic) acid and Pluronic F127 as carrier materials, with Au-Fe 2 C Janus nanoparticles serving as photothermal and ferroptosis agents, and sorafenib (SRF) as the ferroptosis enhancer. The PFP@Au-Fe 2 C-SRF nanocapsules, designed with an appropriate size, exhibit superior intratumoral accumulation compared to free Au-Fe 2 C nanoparticles, as evidenced by photoacoustic and magnetic resonance imaging. These nanocapsules can degrade within the acidic tumor microenvironment when subjected to laser irradiation, releasing free Au-Fe 2 C nanoparticles. This enables them to penetrate deep into tumor regions and disrupt intracellular redox balance. Under the guidance of imaging, these PFP@Au-Fe 2 C-SRF nanocapsules effectively inhibit tumor growth when exposed to laser irradiation, capitalizing on the synergistic photothermal and ferroptosis effects. This study presents an intelligent formulation based on iron carbide for achieving deep tumor ferroptosis through size-switchable cascade delivery, thereby advancing the comprehension of ferroptosis in the context of tumor theranostics., (© 2023 Wiley-VCH GmbH.)

Currently, there is still an intense demand for a simple and scalable delivery platform for peptide-based cancer vaccines. Herein, a cyclodextrin-based polymer nanovaccine platform (CDNP) is designed for the codelivery of peptides with two immune adjuvants [the Toll-like receptor (TLR)7/8 agonist R848 and the TLR9 agonist CpG] that is broadly applicable to epitope peptides with diverse sequences. Specifically, the cyclodextrin-based polymers are covalently linked to epitope peptides via a bioreactive bond-containing cross-linker (PNC-DTDE-PNC) and then physically load with R848 and CpG to obtain CDNP. The CDNP efficiently accumulats in the lymph nodes (LNs), greatly facilitating antigen capture and cross-presentation by antigen-presenting cells. The immunogenicity of the epitope peptides is significantly enhanced by the codelivery and synergy of the adjuvants, and the CDNP shows the ability to inhibit tumor progression in diverse tumor-bearing mouse models. It is concluded that CDNP holds promise as an optimized peptide-based cancer vaccine platform., (© 2023 Wiley-VCH GmbH.)

Zinc oxide nanoparticles (ZnO-NPs) are one of the most widely used nanomaterials with excellent chemical and biological properties. However, their widespread application has led to increased risk to the natural environment and public health. A growing number of studies have shown that ZnO-NPs deposited in target organs interact with internal barriers to trigger injurious responses. The underlying mechanism of ZnO-NPs on the blood-milk barrier dysfunction remains to be understood. Our results revealed that excessive accumulation of ZnO-NPs induced histopathological injuries in the mammary gland, leading to the distribution of ZnO-NPs in the milk of lactating mice. A prominent diffusion of blood-milk barrier permeability marker, albumin-fluorescein isothiocyanate conjugate (FITC-albumin) was observed at cell-cell junction after ZnO-NPs exposure. Meanwhile, ZnO-NPs weakened the blood-milk barrier function by altering the expression of tight junction proteins. The excessive accumulation of ZnO-NPs also induced inflammatory response by activating the NF-κB and MAPK signaling pathways, leading to the dysfunctional blood-milk barrier. Furthermore, we found that ZnO-NPs led to increased iron accumulation and lipid oxidation, thus increasing oxidative injury and ferroptosis in mammary glands. These results indicated that ZnO-NPs weaken the integrity of the blood-milk barrier by directly affecting tight junctions and cellular injury in different ways., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare no competing financial interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Biomedical micro/nanorobots as active delivery systems with the features of self-propulsion and controllable navigation have made tremendous progress in disease therapy and diagnosis, detection, and biodetoxification. However, existing micro/nanorobots are still suffering from complex drug loading, physiological drug stability, and uncontrollable drug release. To solve these problems, micro/nanorobots and nanocatalytic medicine as two independent research fields were integrated in this study to achieve self-propulsion-induced deeper tumor penetration and catalytic reaction-initiated tumor therapy in vivo. We presented self-propelled Janus nanocatalytic robots (JNCRs) guided by magnetic resonance imaging (MRI) for in vivo enhanced tumor therapy. These JNCRs exhibited active movement in H 2 O 2 solution, and their migration in the tumor tissue could be tracked by non-invasive MRI in real time. Both increased temperature and reactive oxygen species production were induced by near-infrared light irradiation and iron-mediated Fenton reaction, showing great potential for tumor photothermal and chemodynamic therapy. In comparison with passive nanoparticles, these self-propelled JNCRs enabled deeper tumor penetration and enhanced tumor therapy after intratumoral injection. Importantly, these robots with biocompatible components and byproducts exhibited biosecurity in the mouse model. It is expected that our work could promote the combination of micro/nanorobots and nanocatalytic medicine, resulting in improved tumor therapy and potential clinical transformations.

Cancer cell membranes (CCMs) have emerged as advanced cancer treatment vaccines to boost the immune response against cancer and have shown great potential in cancer immunotherapy. However, the CCM vaccine confronts the challenges of a weak and short immune response, ascribed to the immune escape and low accumulation of the CCM in antigen presentation cells (APCs). To overcome these shortcomings, we devised a "Trojan horse" CCM nano-vaccine delivered by layered double hydroxide (LDH) nanoparticles with mannose targeting and bovine serum albumin (BSA) coating to overcome the immune escape challenge, efficiently boosting the immune response to cancer cells. This "Trojan horse" CCM nano-vaccine, named LGCMB, is constructed by assembling the CCM antigen on CpG-LDH (LG), followed by mannose-BSA coating for the APC target and BSA coating to mask immune-escape protein on the CCM. The in vitro cellular uptake and maturation data have clearly shown that the BSA coating strategy with mannose as a "Trojan horse" efficiently targeted APCs (macrophages and DCs) and effectively inhibited the immune escape of the CCM, competently stimulating the APC maturation. Moreover, LGCMB can migrate to the draining lymph nodes (LNs) and trigger tumor-specific CD8 + T cell responses in vivo . As expected, the LGCMB nano-vaccine significantly suppressed tumor growth in vivo , showing great potential as a precision cancer vaccine.

Although traditional nanomedicines have enhanced the therapeutic efficacy and improved the survival quality of cancer patients, random drug release and drug resistance are deep-rooted problems hindering their clinical application. A precise nanoplatform combing chemotherapy and photodynamic therapy (PDT) is developing as a new therapeutic strategy to overcome the above challenges. Herein, a novel supramolecular nanomedicine is ingeniously constructed for in situ self-boosting cancer photochemotherapy. Hydrophilic polyethylene glycol (PEG) chains or β-cyclodextrin (β-CD) hosts are first conjugated onto tetraphenyl porphyrin (TCPP) to improve the solubility of TCPP and decrease their π-π stacking interactions, guaranteeing a high-efficiency PDT. Then, two camptothecin (CPT) molecules are linked together via a reactive oxygen species (ROS)-responsive thioketal bond, which averts the premature burst release of CPT and realizes in situ drug release at the tumor site where PDT is performed, resulting in an enhanced chemotherapy. Benefiting from the collaboration of host-guest complexation between β-CD and CPT, multiple intermolecular hydrogen bonds of β-CD, π-π stacking interactions among CPT and TCPP as well as PEG shell protection, a prolonged blood circulation time, and a selective tumor accumulation are acquired, which facilitate the synergistic photochemotherapy and bring a pre-eminent antitumor response with a low systemic toxicity.

Direct hypoxia alleviation and lactate depletion in the tumor microenvironment (TME) are promising for effective cancer therapy but still very challenging. To address this challenge, the current research directly reshapes the TME for inhibiting tumor growth and activating the antitumor immunity using a drug-free nanozyme. Herein, the acid-sensitive nanozymes were constructed based on peroxidized layered double hydroxide nanoparticles for O 2 self-supply and self-boosted lactate depletion. The coloading of partially cross-linked catalase and lactate oxidase enabled the acid-sensitive nanozymes to promote three reactions, that is, (1) H 2 O 2 generation from MgO 2 hydrolysis (30% at pH 7.4 vs 63% at pH 6.0 in 8 h); (2) O 2 generation from H 2 O 2 (12% at pH 7.4 vs 21% at pH 6.0 in 2 h); and (3) lactate depletion by in situ generated O 2 (50% under hypoxia vs 75% under normoxia in 24 h in vitro) in parallel or tandem. These promoted reactions together efficiently induced colon cancer cell apoptosis under the hypoxic conditions, significantly inhibited tumor growth (>95%), and suppressed distant tumor growth upon seven administrations in every 3 days and moreover transformed the immunosuppressive tumor into "hot" one in the colon tumor-bearing mouse model. This is the first example for a nanozyme that supplies sufficient O 2 for hypoxia relief and lactate depletion, thus providing a new insight into drug-free nanomaterial-mediated TME-targeted cancer therapy.

Immune checkpoint inhibitors have achieved significant clinical success but are still suffering from inadequate immune activation. It is worth noting that manganese as a nutritional inorganic trace element is closely associated with immune activation to fight against tumor growth and metastasis via the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway. Herein, we designed hollow mesoporous silica-coated MnO nanoparticles (NPs), followed by conjugation of tumor homing peptide iRGD (CRGDKGPD). The obtained NPs (MnO@mSiO 2 -iRGD NPs) were applied to magnetic resonance imaging (MRI)-guided tumor immune-chemodynamic combination therapy, in which MnO NPs can be harnessed for cGAS-STING pathway-activated immunotherapy, Fenton-like reaction-induced reactive oxygen species upregulation, and T 1 -weighted MRI. The rough surface and large cavities of the mSiO 2 shell promote cellular uptake and MnO NPs delivery. Meanwhile, it was found that MnO@mSiO 2 -iRGD NPs would dissociate under an acid environment, resulting in tumor specificity of MRI and exogenous Mn 2+ release. Our results revealed that these pH-responsive biodegradable MnO@mSiO 2 -iRGD NPs synergized with α-PD-1 (PD-1 = programmed cell death-1) blocking antibody to highly elicit cytotoxic T lymphocyte infiltration and restrict melanoma progression and metastasis, which were envisioned as a promising candidate for tumor theranostics.

Immunological checkpoint inhibitors provide a revolutionary method for cancer treatment. However, due to low tumor mutations and insufficient infiltration of immune cells into the tumor microenvironment, 85% of colorectal cancer patients cannot respond to checkpoint blockade immunotherapy. In this study, tumor microenvironment-responsive deformable nanoparticles (DMP@NPs) were rationally designed to improve immunotherapy by synergistically modulating the immune tumor microenvironment. DMP@NPs self-assemble from a newly synthesized tumor acidity responsive polypeptide checkpoint inhibitor polymer (PEG-DMA- D PPA-1) with immunogenic cell death (ICD) enhanced combination drugs containing a certain proportion of mitoxantrone (MITX) and proanthocyanidins (PC). Upon tumor acidity-triggered cleavage of PEG-DMA- D PPA-1, DMP@NPs undergo special "sphere-ring deformation" dissociation, gradually releasing polypeptide checkpoint inhibitor D PPA-1, MITX and PC. MITX/PC in vitro synergistically triggers higher ICD with the release of the high mobility group box-1 (HMGB-1) and calreticulin (CRT). After intravenous injection of DMP@NPs, the local tumor microenvironment of CT26 tumor-bearing mice was reprogrammed, and dendritic cell activation and T cell infiltration were significantly increased. Most importantly, the synergistic immune nanodrug DMP@NPs improved the efficacy of colorectal cancer immunotherapy and reduced toxicity and side effects for the immune organs.

Cancer vaccines have attracted increasing attention for their application in tumor immunotherapy. DNA vaccines are one of them that have been proven very promising with the advantages of safety, rapid design, and low cost. However, the low stability, ineffective cell internalization, and low immunostimulation hinder their wide application. Thus, developing targeted and safe systems to effectively deliver DNA vaccines becomes a vital step. In this study, we report the development of mannose- and bisphosphonate (BP)-modified calcium phosphate (CP) nanoparticles (NPs) as efficient vaccine delivery vehicles by targeting C-type lectin receptors (CLRs) on antigen-presenting cells (APCs). Using a model antigen ovalbumin (OVA)-encoded plasmid DNA (pOVA) as a model vaccine, we demonstrate that mannose-modified and BP-stabilized CP (MBCP) nanoparticles are mono-dispersed for enhanced uptake by APCs and subsequently induce OVA antigen presentation and immunostimulation. Mice immunized with MBCP-pOVA nanovaccines show a significantly stronger anti-OVA antibody response with a quicker IgG1 and IgG2a antibody production than unmodified NPs. Moreover, MBCP-pOVA immunization significantly inhibits the growth of OVA-expressing E.G7 tumor cells in C57BL/6J mice. Our data collectively suggest that the modifications to enhance the stability and targeting ability of MBCP NPs are essential for effective delivery of DNA vaccines and promote robust anti-tumor immunity.

Cancer metastasis is the main cause of chemotherapeutic failure. Inhibiting the activity of matrix metalloproteinases (MMPs) is a common strategy for reducing metastasis. However, broad-spectrum MMP-inhibitors (MMPI) may cause undesired side effects. Here, we screened a selective MMP2 inhibitor (CCKIGLFRWR) and linked it with doxorubicin (DOX) to produce an amphiphilic peptide-drug conjugate (PDC). Then novel core-shell nanoparticles were self-assembled from PDC core and modified polylysine (MPL) shell. When the particles were passively targeted to the tumor site, the PDC core was exposed for charge switch of the MPL shell, aggregated for its transformation behavior, and specially adhered to the cell membrane. The disulfide bond between the MMPI peptide and DOX was broken via a low concentration of glutathione-mediated reduction in tumor microenvironment. DOX could effectively enter the tumor cells. Meanwhile, the MMPI peptide could selectively inhibit the activity of the MMP2 and effectively inhibit tumor metastasis.

Urban runoff conveys contaminants including titanium dioxide (TiO 2 ), widely used as engineered nanoparticles (e.g., 1-100 nm) and pigments (e.g., 100-300 nm) in the urban environment, to receiving surface waters. Yet, the concentrations of TiO 2 engineered particles (e.g., engineered nanoparticles and pigments) in urban runoff has not been determined due to difficulties in distinguishing natural from engineered TiO 2 particles in environmental matrices. The present study examines the occurrence and estimates the concentrations of TiO 2 engineered particles in urban runoff under wet- and dry-weather conditions. Urban runoff was collected from two bridges in Columbia, South Carolina, USA under wet-weather conditions and from the Ballona Creek and Los Angeles (LA) River in Los Angeles, California, USA under dry-weather conditions. The concentrations of TiO 2 engineered particles were determined by mass balance calculations based on shifts in elemental concentration ratios in urban runoff relative to natural background elemental ratios. Elemental ratios of Ti to Nb in urban runoff were higher than the natural background ratios, indicating Ti contamination. The occurrence of TiO 2 engineered particles was further confirmed by transmission electron microscopy coupled with energy dispersive spectroscopy. The concentration of TiO 2 engineered particles in urban runoff was estimated to be in the range of 5-150 μg L -1 . Therefore, this study identifies urban runoff as a previously unaccounted source of TiO 2 engineered particle release to the environment, which should be included in engineered nanoparticle fate modeling studies and in estimating environmental release of engineered nanoparticles., Competing Interests: Declaration of competing interest The authors declare no competing interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Titanium dioxide nanoparticles (TiO 2 NPs) are subjected to various transformation processes (chemical, physical and biological processes) in the environment, potentially affecting their bioavailability and toxic properties. However, the size variation of TiO 2 NPs during aging process and subsequent effects in mammalian cells are largely unknown. The aim of this study was to illustrate the adverse effects of TiO 2 NPs in different sizes (5, 15 and <100 nm) during aging process on human-hamster hybrid (A L ) cells. There was an aging-time dependent enhancement of average hydrodynamic size in TiO 2 NPs stock suspensions. The cytotoxicity of fresh TiO 2 NPs increased in a size-dependent manner; in contrast, their genotoxicity decreased with the increasing sizes of NPs. No significant toxicity difference was observed in cells exposed to either fresh or 60 day-aged TiO 2 NPs. Both Fresh and aged TiO 2 NPs efficiently induced mitochondrial dysfunction and activated Caspase-3/7 in a size-dependent manner. Using mitochondrial-DNA deficient (ρ 0 ) A L cells, we further discovered that mitochondrial dysfunction made significant contribution to the size-dependent toxicity induced by TiO 2 NPs during the aging process. Taken together, our data indicated that TiO 2 NPs could significantly induced the cytotoxicity and genotoxicity in an aging time-independent and size-dependent manner, which were triggered by mitochondrial dysfunction. Our study suggested the necessity to include size as an additional parameter for the cautious monitoring of TiO 2 NPs disposal before entering the environment., (Copyright © 2019. Published by Elsevier B.V.)

Combination therapy with multiple chemotherapeutic agents is the main approach for cancer treatment in the clinic. Polyphenol-based materials are found in our diet, demonstrate good biocompatibility, and prevent numerous diseases. In this study, we encapsulate two drugs in a single polyphenol-based polymer with Fe 3+ or Mn 2+ ions as the cross-linker for cancer therapy. The combination index of two drugs is an essential parameter to evaluate drug combinations. The amphiphilic polymer poly(ethylene glycol)-block-polydopamine (PEG-PDA) was prepared by RAFT polymerization. The nanoparticles were prepared via self-assembly with Fe 3+ or Mn 2+ ions. Both doxorubicin (DOX) and simvastatin (SV) were encapsulated in the core of the nanoparticles. The cell viability and combination index were evaluated in vitro. The tumor accumulation of the nanoparticles was investigated by positron-emission tomography (PET) and magnetic resonance (MR) imaging. The as-prepared nanoparticles exhibited high drug loading capacity. The drug loaded nanoparticles could kill cancer cells effectively with a combination index <1. Both PET and MRI revealed that the nanoparticles showed long blood circulation time and high tumor accumulation. The nanoparticles could inhibit tumor inhibition via intravenous injection of nanoparticles. The polyphenol-based nanoplatform may serve as a promising theranostic candidate for clinical application.

This study was aimed at improving oral bioavailbility and reducing the food effect of cinacalcet hydrochlorde (CINA), a poorly soluble drug for the treatment of chronic kidney disease, by preparing its nanocrystals (NCs) utilizing the precipitation-ultrasonication method. Based on the single factor method and Box-Behnken design, with the particle size and polydispersity index (PDI) as indexes, the optimal formulation was achieved. It was investigated that the particle size and PDI of the NCs prepared on the basis of optimal formulation were 244 ± 2 nm and 0.168 ± 0.001, respectively. The NCs were solidificated by lyophilization. Scanning electron microscopy, differential scanning calorimetry and x-ray powder diffraction were used to characterize the CINA-NCs, and there was no crystalline change during preparation and lyophilization. The CINA-NCs capsules prepared with 30% (w/v) MCC, 8% (w/v) CCNa and 2% (w/v) talcum powder by orthogonal experimental design presented an enhanced in vitro dissolution rate in four media compared with commercial tablets Sensipar® and raw material. The raw material, blank NCs and CINA-NCs were confirmed to be non-toxic to Caco-2 cells when the drug concentration was below 250 μg ml -1 . In the in vivo pharmacokinetic study, the C max (the peak concentration of CINA in plasma) and AUC 0-t (area under curve by trapezoidal area method) of the CINA-NCs capsules were approximately 1.90-fold and 1.64-fold greater than that of Sensipar® in the fasted state. Overall, this nanotechnology is a promising way to optimize the dosage form of CINA oral administration.

Functionalized nanomaterials with near-infrared (NIR) responsive capacity are quite promising for theranostic treatment of tumors, but formation of NIR responsive nanomaterials with enhanced theranostic ability and excellent biocompatibility is still very challenging. Herein, PEGylated indocyanine green (ICG)-loaded polypyrrole nanoparticles (PPI NPs) were designed and successfully formed through selecting polydopamine as the linkage between each component, demonstrating enhanced NIR responsive theranostic ability against tumor. By combining in vitro cell study with in vivo assay, the formed PPI NPs were proven to be fantastically biocompatible while effectively internalization in HeLa cells and retention in HeLa tumor were demonstrated by in vitro flow cytometry/confocal measurement and in vivo photoacoustic imaging assay. With the guidance of photoacoustic imaging, successful photothermal ablation of tumor was achieved by treatment with PPI NPs plus laser, which was much more effective than the group treated with NPs free of ICG. The combined enhanced photoacoustic and photothermal effect is mainly ascribed to the functionalized polypyrrole nanoparticles, which could accumulate in the tumor site more effectively with a relatively longer retention time taking advantage of the nanomaterial-induced endothelial leakiness phenomenon. All these results demonstrating that this designed PPI NPs possessing enhanced NIR responsive property hold great promise for tumor NIR theranostic applications.

Puerarin (PUE) is the most abundant isoflavonoid in kudzu root. It is widely used as a therapeutic agent for the treatment of cardiovascular diseases. However, the short elimination half-life, poor-bioavailability, and acute intravascular hemolysis of PUE are the main obstacles to its widespread clinical applications. Whereas PEG-PE micelles possess the ability to release medicine slowly, enhance the cellular uptake of drugs and improve their biocompatibility. Therefore, it was aim to fabricate puerarin-loaded PEG-PE (PUE@PEG-PE) micelles to improve the pharmaceutical properties of drugs. It can be observed from the TEM images that PUE@PEG-PE micelles appeared obvious core-shell structure and remained well-dispersed without aggregation and adhesion. PUE was successfully embedded in the core of PEG-PE micelles, which was confirmed by FT-IR and 1 H NMR spectra. In vitro studies showed that PUE@PEG-PE micelles exhibited a sustained release behavior in pH 7.4 PBS buffer and decreased hemolysis rate of PUE. Compared with PUE, PUE@PEG-PE micelles showed a 3.2-fold increase in the half-life of PUE and a 1.58-fold increase in bioavailability. In addition, the PUE@PEG-PE micelles exerted enhanced protective effect against isoprenaline-induced H9c2 cells apoptosis compared with PUE, as evident by decreased percentage of Hoechst-positive cells, Caspase 3 activity, Bax expression, and increased Bcl-2 expression. Notably, the PEG-PE micelles exhibited favorable cellular uptake efficiency on H9c2 cells, and this may account for their enhanced anti-apoptotic effect of the incorporated drug. Altogether, the PUE@PEG-PE micelles were not only able to control the drug release but also offered promise to enhance the pharmacokinetic and pharmacodynamic potential of PUE.

Unintentionally released titanium dioxide nanoparticles (TiO 2 NPs) may co-occur with pre-existing heavy metal pollutants in aquatic environments. However, the interactions between NPs and heavy metals (HMs) and their co-effects in living organisms are largely unknown. The aim of this investigation was to illustrate the influence of TiO 2 NPs (5 and 15 nm) on the bioaccumulation and toxicity of cadmium (Cd), arsenate (As(III)), and nickel (Ni) in Caenorhabditis elegans (C. elegans) during the process of sedimentation in aquatic environment. Our data showed that HMs accelerated the aggregation of TiO 2 NPs. The rapid aggregation and sedimentation of TiO 2 NPs changed the vertical distribution of HMs through adsorption and induced increased and prolonged exposure of benthic species. Aggregate particle size along with ionic strength were the major factors affecting the rate of sedimentation. TiO 2 NPs at non-toxic concentrations efficiently enhanced the bioaccumulation and reproductive toxicity of HMs to C. elegans in a dose- and size-dependent manner; however, the effect of TiO 2 NPs on As(III) was obviously lower than that on two valence metals. These data provided clear evidence that TiO 2 NPs could serve as environmental regulators to significantly facilitate the toxicity and the accumulation of HMs in C. elegans, indicating that the interaction and fate of TiO 2 NPs and HMs on their co-toxic responses during the sedimentation should be considered as a necessary and integral part of risk assessment in the ecological system., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Although demanding, the development of multifunctional theranostic nanoplatforms is attracting considerable worldwide interest. Herein, a theranostic nanoplatform with multifunctions based on polydopamine (PDA) nanoparticles (NPs) was developed, owning dual-imaging and dual-therapy functions for cancer theranostic applications. PDA NPs were generated using a facile polymerization method under alkaline conditions, followed by poly(ethylene glycol) (PEG) modification. Then, the obtained NPs were loaded with IR820 and Fe 3+ ions to produce the final PEGylated PDA/IR820/Fe 3+ (PPIF) NPs. The PPIF NPs thus generated displayed increasingly brighter photoacoustic and magnetic resonance signals with increasing NP concentration and were demonstrated to be cytocompatible and effectively taken up and internalized into HeLa cells. Under near-infrared light irradiation, PPIF NPs can produce heat and reactive oxygen species for photothermal/photodynamic combined cancer therapy. In this study, the versatility of PDA NPs was demonstrated to be promising as a multifunctional nanoplatform for potential cancer theranostic applications.

Carbon monoxide (CO) is recognized as a biologically essential gaseous neurotransmitter that modulates many physiological processes in living subjects. Currently reported fluorescent probes for CO imaging in cells basically utilize palladium related chemistry which requires complicated synthetic work. Herein we provide a new strategy to construct a fluorescent nanoprobe, NanoCO-1, based on the Forster resonance energy transfer (FRET) mechanism by entrapping the existing dirhodium complex as the energy acceptor and the CO recognition part, and a commonly used nitrobenzoxadiazole (NBD) dye as energy donor into a micelle formed by self-assembly. The exchange of ligands in the dirhodium complex by CO in the nanoprobe disrupts the FRET and leads to the turn-on of fluorescence. The merits of NanoCO-1 including good biocompatibility, selectivity, photostability, and low cytotoxity, render this nanoprobe ability to track CO in living cells, zebrafish embryo, and larvae. Our straightforward approach can be extended to establish the CO fluorescent probes based on adsorption of CO on a variety of metal derivatives.

Inhalation administration, compared with intravenous administration, significantly enhances chemotherapeutic drug exposure to the lung tissue and may increase the therapeutic effect for pulmonary anticancer. However, further identification of cancer cells after lung deposition of inhaled drugs is necessary to avoid side effects on normal lung tissue and to maximize drug efficacy. Moreover, as the action site of the major drug was intracellular organelles, drug target to the specific organelle is the final key for accurate drug delivery. Here, we designed a novel multifunctional nanoparticles (MNPs) for pulmonary antitumor and the material was well-designed for hierarchical target involved lung tissue target, cancer cell target, and mitochondrial target. The biodistribution in vivo determined by UHPLC-MS/MS method was employed to verify the drug concentration overwhelmingly increasing in lung tissue through inhaled administration compared with intravenous administration. Cellular uptake assay using A549 cells proved the efficient receptor-mediated cell endocytosis. Confocal laser scanning microscopy observation showed the location of MNPs in cells was mitochondria. All results confirmed the intelligent material can progressively play hierarchical target functions, which could induce more cell apoptosis related to mitochondrial damage. It provides a smart and efficient nanocarrier platform for hierarchical targeting of pulmonary anticancer drug. So far, this kind of material for pulmonary mitochondrial-target has not been seen in other reports.

Photodynamic therapy (PDT) is a novel treatment modality that is under intensive preclinical investigations for a variety of diseases, including cancer. Despite extensive studies in this area, selective and effective photodynamic agents that can specifically accumulate in tumors to reach a therapeutic concentration are limited. Although recent attempts have produced photosensitizers (PSs) complexed with various nanomaterials, the tedious preparation steps and poor tumor efficiency of therapy hamper their utilization. Here, we developed a CD44-targeted nanophotodynamic agent by physically encapsulating a photosensitizer, Ce6, into a hyaluronic acid nanoparticle (HANP), which was hereby denoted HANP/Ce6. Its physical features and capability for photodynamic therapy were characterized in vitro and in vivo. Systemic delivery of HANP/Ce6 resulted in its accumulation in a human colon cancer xenograft model. The tumor/muscle ratio reached 3.47 ± 0.46 at 4 h post injection, as confirmed by fluorescence imaging. Tumor growth after HANP/Ce6 treatment with laser irradiation (0.15 W/cm 2 , 630 nm) was significantly inhibited by 9.61 ± 1.09-fold compared to that in tumor control groups, which showed no change in tumor growth. No apparent systemic and local toxic effects on the mice were observed. HANP/Ce6-mediated tumor growth inhibition was accessed and observed for the first time by 18 F-fluoro-2-deoxy-d-glucose positron emission tomography as early as 1 day after treatment and persisted for 14 days within our treatment time window. In sum, our results highlight the imaging properties and therapeutic effects of the novel HANP/Ce6 theranostic nanoparticle for CD44-targeted PDT cancer therapy that may be potentially utilized in the clinic. This HANP system may also be applied for the delivery of other hydrophobic PSs, particularly those that could not be chemically modified.

Despite recent advances in the understanding of fundamental cancer biology, cancer remains the second most common cause of death in the United States. One of the primary factors indicative of high cancer morbidity and mortality and aggressive cancer phenotypes is tumors with a low extracellular pH (pHe). Thus, the ability to measure tumor pHe in vivo using noninvasive and accurate techniques that also provide high spatiotemporal resolution has become increasingly important and is of great interest to researchers and clinicians. In an effort to develop a pH-responsive magnetic resonance imaging (MRI) contrast agent (CA) that has the potential to be used to measure tumor pHe, well-defined pH-responsive polymers, synthesized via reversible addition-fragmentation chain transfer polymerization, were attached to the surface of gadolinium-based nanoparticles (GdNPs) via a "grafting to" method after reduction of the thiocarbonylthio end groups. The successful modification of the GdNPs was verified by transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and dynamic light scattering. The performance of the pH-responsive polymer modified GdNPs was then evaluated for potential use as smart MRI CAs via monitoring the relaxivity changes with changing environmental pH. The results suggested that the pH-responsive polymers can be used to effectively modify the GdNPs surface to prepare a smart contrast agent for MRI.

One mechanism of photodynamic therapy (PDT) for the ablation of tumors is to induce apoptosis. Visualization of apoptosis during PDT in real-time is of great benefit for predicting and evaluating therapeutic outcomes. Herein, we engineered a highly stable and sensitive caspase-3 ferritin activatable probe (FABP/ZnPc) for simultaneous delivery of a photosensitizer (ZnPc) and real-time visualization of apoptosis during PDT. Upon near-infrared (NIR) light irradiation, ZnPc becomes active and initiates apoptosis, upon which the outer layer of the FABP/ZnPc is degraded by the apoptotic marker, caspase-3, to boost strong fluorescent signals, ultimately allowing real-time imaging of apoptosis. Our results demonstrate the utility of FABP/ZnPc as a tool for PDT and simultaneous imaging of caspase-3 activation in vitro and in vivo. Overall, the ability of FABP/ZnPc to image apoptosis during PDT will not only facilitate optimizing and personalizing the PDT strategy but is also important for understanding the mechanisms of PDT.

A dually responsive nanocarrier with multilayer core-shell architecture was prepared based on Fe(3)O(4)@SiO(2) nanoparticles coated with mPEG-poly(l-Asparagine). Imidazole groups (pK(a)∼6.0) were tethered to the side chains of poly(l-Asparagine) segments by aminolysis. These nanoparticles were expected to be sensitive to both magnetic field and pH environment. The obtained materials were characterized with FTIR, dynamic light scattering, ζ-potential, TEM, TGA and hysteresis loop analysis. It was found that this Fe(3)O(4)@SiO(2)-polymer complex can form nano-scale core-shell-corona trilayer particles (∼250 nm) in aqueous solution. The Fe(3)O(4)@SiO(2), poly(L-Asparagine) and mPEG segments serve as a super-paramagnetic core, a pH-sensitive shell, and a hydrophilic corona, respectively. An antitumor agent, doxorubicin (DOX), was successfully loaded into the nanocarrier via combined actions of hydrophobic interaction and hydrogen bonding. The drug release profiles displayed a pH-dependent behavior. DOX release rate increased significantly as the ambient pH dropped from the physiological pH (7.4) to acidic (5.5). This is most likely due to protonation and a change in hydrophilicity of the imidazole groups in the poly(l-Asparagine) segments. This new approach may serve as a promising platform to formulate magnetic targeted drug delivery systems., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Herein, a N-doped carbon nanotube encapsulated FeF3 nanoparticle (FeF3@N-CNTs) composite was developed via in situ pyrolysis and gas-phase fluorination strategies. The 3D carbon constrained scaffold enhances conversion reaction kinetics and effectively suppresses significant volume changes in the FeF3 cathode during cycling. Consequently, FeF3@N-CNTs exhibits excellent rate capability and maintains a high discharge capacity of 110.6 mA h g−1 after 5000 cycles at 2 A g−1. It is believed that this study presents an innovative strategy for the development of long-cycling conversion-type cathode materials. [ABSTRACT FROM AUTHOR]

Nowadays, bacterial infection is regarded as a serious threat to humankind, which needs to be taken care of. The emergence of antibiotic resistance and multidrug resistance (MDR) is rendering this situation more troublesome. However, several alternative treatment regimens have aided such diseases quite well in the recent past, among which dynamic antibacterial therapies combat this situation quite well. Among various dynamic therapies, piezodynamic therapy is a very recent avenue, in which mechanical stimuli have been exploited to treat bacterial infections. Herein, piezo-active bismuth ferrite-loaded poly(vinylidene fluoride-co-hexafluoropropylene) polymer has been utilized to eradicate gram-positive bacteria (E. faecalis) and gram-negative bacteria (E. coli). The sample has been designed in a free-standing membrane form, which, under soft ultrasound (~10 kHz), generates reactive radicals to ablate bacteria. Initially, the structure and morphology of the membrane have been substantiated by using X-ray diffraction and scanning electron microscopy methods; besides, Fourier transform infrared spectrum of the sample depicts a tremendously high value of polarizability and further confirms the piezo-activity of the membrane. More than 99% of E. coli and E. faecalis have been successfully eradicated within 30 min of ultrasound. Moreover, the solid-state structure and hydrophobic nature of the membrane help us to reuse it in a cyclic manner, which is possibly reported herein for the very first time. This novel membrane could be deployed in healthcare systems and pigment industries and could be exploited as a self-cleaning material. [ABSTRACT FROM AUTHOR]

The rupture of atherosclerosis (AS) vulnerable plaque is the major cause of fatal arterial thrombosis related diseases. The lipid dysbolism and pro-inflammatory microenvironment are considered two main driving factors for plaque rupture. Herein, a "two-pronged" nanosystem LCS-Se/Res was designed to efficiently stabilize AS plaques, by precisely regulating lipid metabolism and inflammatory microenvironment. LCS-Se/Res was constructed with the core of resveratrol (Res) loaded selenium (Se) nanoparticles (NPs), and the shell (LCS) of targeting peptide (LSIPPKA) modified chitosan (CS). This system was stable in blood circulation. When it arrived at the plaque site, LCS-Se/Res could actively recognize the highly expressed lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) receptor and accumulate there. Thereafter, Res was released from LCS-Se nanocarriers in situ by responding to acidic plaque microenvironment. On the one hand, Res increased autophagy flux in damaged endothelial cells by activating cAMP-PKA-AMPK-SIRT1 signaling pathway to promote lipid degradation. Interestingly, LCS-Se also promoted cholesterol efflux to improve lipid metabolism. On the other hand, fixed-point separated Res and LCS-Se synergistically improved plaque inflammatory microenvironment by reversing macrophage phenotype (M1 to M2) and alleviating plaque oxidative stress. Pharmacodynamics result proved that the plaque vulnerability index (VI) decreased from 1.39 ± 0.282 to 0.108 ± 0.02 after LCS-Se/Res treatment. In short, this study provided a new therapeutic strategy for the atherosclerosis through the two-pronged approach. [ABSTRACT FROM AUTHOR]

Extending shelf life and maintaining the high quality of food are arduous challenges. In this study, the self-assembly properties of zein were used to load carvacrol essential oil, and then sodium caseinate was selected as a stabilizer to fabricate carvacrol-loaded composite nanoparticles. The results showed that the composite nanoparticles had a high encapsulation efficiency for carvacrol (71.52–80.09%). Scanning electron microscopy (SEM) indicated that the carvacrol-loaded composite nanoparticles were spherical and uniformly distributed, with particle sizes ranging from 80 to 220 nm. First and foremost, the carvacrol-loaded nanoparticles exhibited excellent water-redispersibility, storage-stability, and antioxidant properties, as well as antibacterial properties against Staphylococcus aureus and Escherichia coli. Benefiting from the antimicrobial and antioxidative abilities, the films with carvacrol-loaded composite nanoparticles effectively inhibited food spoilage and prolonged the shelf-life of cherry tomatoes and bananas. Therefore, carvacrol-loaded composite nanoparticles may have potential application prospects in the food industry. [ABSTRACT FROM AUTHOR]

purpose of this study was to prepare and characterize a lipid magnetic ball modified with KRAS antibodies on the surface and to isolate circulating tumor cells of colorectal cancer with KRAS mutations. Methods: The microemulsion method was used to form lipid bilayers to encapsulate Fe3O4 nanoparticles with superparamagnetism to form lipid magnetic balls, and KRAS antibodies were formed on the surface to form KRAS immune lipid magnetic balls. Results: Compared with traditional EpCAM antibody-modified lipid magnetic balls, it can effectively improve the capture ability of colorectal cancer circulating tumor cells with KRAS mutation, the capture rate reaches 92.9%, and the capture results are consistent with clinical diagnosis and pathology. Conclusion: Our results showed that KRAS antibody-modified lipid magnetic balls can be used in the diagnosis and treatment of KRAS colorectal cancer. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnO NPs) are being produced abundantly and applied increasingly in various fields. The special physicochemical characteristics of ZnO NPs make them incline to undergo physicochemical transformation over time (aging), which modify their bioavailability and toxicity. However, the subcellular targets and the underlying molecular mechanisms involved in the genotoxicity induced by ZnO NPs during aging process are still unknown. This study found that the acute cytotoxic effects of fresh ZnO NPs was largely regulated by mitochondria-dependent apoptosis, which the level of cleaved Caspase-3 and mitochondria damage were significantly higher than that of 60-day-aged ZnO NPs. In contrast, aged ZnO NPs induced more reactive oxygen species (ROS) production and endoplasmic reticulum (ER) stress marker protein (BIP/GRP78) expression and their genotoxicity could be dramatically suppressed by either ROS scavengers (dimethyl sulfoxide, catalase, and sodium azide) or ER stress inhibitor (4-phenylbutyrate). Using mitochondrial-DNA deficient (ρ 0) AL cells, we further found that ER stress induced by aged ZnO NPs was triggered by ROS generated from mitochondria, which eventually mediated the genotoxicity of aged NPs. Our data provided novel information on better understanding the contribution of subcellular targets to the genotoxic response of ZnO NPs during the aging process. [ABSTRACT FROM AUTHOR]

Typical biological processing is often challenging for removing ammonia nitrogen and phosphate from swine wastewater due to inhibition of high ammonia on activity of microorganisms, exhaustion of time, and low efficiency. In this study, a physicochemical process by combining ammonia stripping with struvite precipitation has been tested to simultaneously remove ammonia nitrogen, phosphate, and chemical oxygen demand (COD) from digested swine wastewater (DSW) with high efficiency, low cost, and environmental friendliness. The pH, temperature, and magnesium content of DSW are the key factors for ammonia removal and phosphate recovery through combining stripping with struvite precipitation. MgO was used as the struvite precipitant for NH4+ and PO43− and as the pH adjusted for air stripping of residual ammonia under the condition of 40 °C and 0.48 m3 h−1 L−1 aeration rate for 3 h. The results showed that the removal efficiency of ammonia, total phosphate, and COD from DSW significantly increased with increase of MgO dosage due to synergistic action of ammonia stripping and struvite precipitation. Considering the processing cost and national discharge standard for DSW, 0.75 g L−1 MgO dosage was recommended using the combining technology for nutrient removal from DSW. In addition, 88.03% NH4+-N and 96.07% TP could be recovered from DSW by adsorption of phosphoric acid and precipitation of magnesium ammonium phosphate (MAP). The combined technology could effectively remove and recover the nutrients from DSW to achieve environmental protection and sustainable and renewable resource of DSW. An economic analysis showed that the combining technology for nutrient removal from DSW was feasible. [ABSTRACT FROM AUTHOR]

Unintentionally released titanium dioxide nanoparticles (TiO 2 NPs) may co-occur with pre-existing heavy metal pollutants in aquatic environments. However, the interactions between NPs and heavy metals (HMs) and their co-effects in living organisms are largely unknown. The aim of this investigation was to illustrate the influence of TiO 2 NPs (5 and 15 nm) on the bioaccumulation and toxicity of cadmium (Cd), arsenate (As(III)), and nickel (Ni) in Caenorhabditis elegans ( C. elegans ) during the process of sedimentation in aquatic environment. Our data showed that HMs accelerated the aggregation of TiO 2 NPs. The rapid aggregation and sedimentation of TiO 2 NPs changed the vertical distribution of HMs through adsorption and induced increased and prolonged exposure of benthic species. Aggregate particle size along with ionic strength were the major factors affecting the rate of sedimentation. TiO 2 NPs at non-toxic concentrations efficiently enhanced the bioaccumulation and reproductive toxicity of HMs to C. elegans in a dose- and size-dependent manner; however, the effect of TiO 2 NPs on As(III) was obviously lower than that on two valence metals. These data provided clear evidence that TiO 2 NPs could serve as environmental regulators to significantly facilitate the toxicity and the accumulation of HMs in C. elegans , indicating that the interaction and fate of TiO 2 NPs and HMs on their co-toxic responses during the sedimentation should be considered as a necessary and integral part of risk assessment in the ecological system. [ABSTRACT FROM AUTHOR]

Sb2WO6/TiO2 composites with different contents of Sb2WO6 were successfully synthesized through a facile hydrothermal method. The Sb2WO6/TiO2 composites were characterized by X-ray diffraction (XRD), UV-visible diffuse reflectance spectra (UV-vis DRS), photoluminescence spectra (PL), scanning electron microscope (SEM) and transmission electron microscope (TEM). Sb2WO6 nanoparticles are distributed uniformly on the surface of TiO2 nanobelts in the prepared Sb2WO6/TiO2 composites. The effect of Sb2WO6 content on the photocatalytic activity of composites is studied by UV-vis DRS and PL. All Sb2WO6/TiO2 photocatalysts show enhanced photocatalytic activity and excellent recycling property for degrading rhodamine B (RhB) under visible light irradiation. The 30% Sb2WO6/TiO2 sample shows the best photocatalytic activity. Its kinetic constant (0·476/h) is 21·6 times higher than that of TiO2. The possible photocatalytic mechanism is discussed according to the trapping experiments of active species. The improved photocatalytic activity for the Sb2WO6/TiO2 catalyst may be attributed to the synergetic effect between Sb2WO6 nanoparticles and TiO2 nanobelts. The enhanced photocatalytic activity and excellent stability make this material a promising candidate for degrading environmental pollutants in the future. [ABSTRACT FROM AUTHOR]

A nanocomposite consisted of Ag nanoparticles and WS nanosheets was prepared by a two-step procedure, in which Ag sol was generated at first, then added into WS nanosheet dispersion to form the nanocomposite via self-assembly. The nanocomposites with different content of Ag nanoparticles were successfully prepared. The results show that Ag nanoparticles with the diameter of 10-20 nm are uniformly distributed on WS nanosheets and not oxidized. All nanocomposites are mesoporous. The specific surface area and the mesoporosity of WS are improved due to the existence of Ag nanoparticles. The specific capacitance of the nanocomposite increases with the increasing content of Ag nanoparticles. The 2000 cycles of charging and discharging were carried out on 20%AgNPs@WS nanocomposite, proving its good cycling performance. It has smaller transfer resistance and internal series resistance than WS nanosheets. This nanocomposite has potential application in supercapacitors. [ABSTRACT FROM AUTHOR]

Ag@Ga-doped ZnO core-shell nanoparticles show excellent SERS sensitivity, stability and repeatability, which is attributed to its rich surface defects, plasmon- and photo-induced charge-transfer effect by its unique core-shell structure. [Display omitted] • Ag@Ga-doped ZnO core-shell nanoparticles were successfully prepared by simple solvothermal method and defect engineering. • Such SERS substrates exhibits high sensitivity, stability and repeatability. • The detection limit of the substrate for pesticide thiram can reach 10−9 M, which is far lower than the national standard. • The Ag@2.6%Ga-ZnO CSNPs can complete catalytic degradation of organic dye molecule R6G within 40 min. • SERS enhanced mechanism was discussed in detail. There has been increasing interest in evolution of semiconductor-based SERS-active substrates to achieve ultrasensitive detection of trace analyte molecules. This work presents a simple solvothermal method and further defect engineering technology to obtain Ag@Ga-doped ZnO core-shell nanoparticles (Ag@n%Ga-ZnO CSNPs), which have both local electromagnetic enhancement from Ag-core and efficient charge transfer enhancement due to the plasmon and photo-induced electrons and numerous deficiency sites after Ga-doping, for achieving ultrahigh detection sensitivity, stability and repeatability. Specifically, the unique Ag@2.6%Ga-ZnO CSNPs exhibited good linearity in the range from 10−6 to 10−12 M for the typical dye analyte rhodamine 6G (R6G), and the limit of detection could be down to 10−12 M. The Raman signal intensity of the Ga-doped core-shell structure was stable after 60 days of storage at room temperature. Moreover, the as-prepared Ag@2.6%Ga-ZnO CSNPs shows excellent signal repeatability as SERS substrate, and the relative standard deviation (RSD) is calculated to be about 9.71%. To illustrate the usefulness for detection of hazardous substance, we showed that such substrate can detect a pesticide, thiram, at a concentration as low as 10−9 M, which is far lower than the national standard. In addition, due to the construction of the core-shell structure and the introduction of Ga-doping, the photoelectric properties of the material have also been greatly improved. Under the irradiation of xenon lamp, the Ag@2.6%Ga-ZnO CSNPs can complete catalytic degradation of organic dye molecule R6G and pesticide molecule thiram within 40 to 50 min. This study demonstrated that the Ag@Ga-doped ZnO core-shell nanoparticles could serve as an effective and versatile SERS platform for reproducible, fast and in-field detection of organic analytes at trace levels. [ABSTRACT FROM AUTHOR]

Abstract: TiO2 nanoparticles with improved photocatalytic activity (TiO2NPs-NaCl(R)) were synthesized through a well controlled sol–gel process in the presence of NaCl. Instead of being incorporated into the lattice of TiO2, the added sodium chloride can be completely removed from the resultant TiO2NPs-NaCl(R) by DI water. The results showed that TiO2NPs-NaCl(R) has 2 times more surface hydroxyl groups than that in TiO2NPs prepared without adding NaCl. Consequently TiO2NPs-NaCl(R) exhibits an enhanced photocatalytic activity for degradation of methylene blue (MB) and HCHO under UV irradiation. This research provides a simple and economic approach to improve photocatalytic performance of TiO2 related materials. [Copyright &y& Elsevier]

[Display omitted] • A new understanding in the active site of CuMnOx catalysts. • CuMnOx catalysts are composed by uniform CuO-Mn 2 O 3 oxide pairs. • Highly isolated CuO nano-particles are essential for CuO-Mn 2 O 3 oxide pairs. • Cu-O-Mn sites are found to be the active sites of CuO-Mn 2 O 3 oxide pairs. The current work provide a new understanding on the active site of CuMnOx catalysts and thus offer a new perspective in the development of highly effective and low cost CuMnOx catalysts for heterogeneous catalytic oxidation reactions. A series of dual-component copper-manganese multi-oxide catalysts (CuMnOx) have been successfully synthesized using a surfactant assisted hydrolysis-hydrothermal method and studied by XRD, N 2 adsorption–desorption test, ICP-AES, SEM, Aberration-corrected HADDF-STEM, HRTEM, FT-IR, Raman, XPS, H 2 -TPR. These CuMnOx catalysts were found to be composed with uniform CuO-Mn 2 O 3 oxide pair structure, in which highly isolated/dispersed CuO species are anchored in the framework of Mn 2 O 3. It was found that the speciation in these CuMnOx catalysts presents a shift from highly isolated or even single Cu2+ oxide species (Cu2+Ox) to CuO nanoclusters and CuO microcrystalline with increasing Cu content. In CO oxidation reaction, which was employed to probe the structure of the CuO-Mn 2 O 3 oxide pairs in these CuMnOx catalysts, the Cu-O-Mn sites in those CuMnOx catalysts with highly isolated or highly dispersed CuO species were found to be highly active. For CuO-Mn 2 O 3 oxide pair catalysts, the highly isolated/dispersed CuO species in Mn 2 O 3 framework is essential to achieve high activity. [ABSTRACT FROM AUTHOR]

Inorganic two-dimensional nanomaterials have been artificially engineered as dynamic nano-assembly drug delivery systems (DNDDSs). Their dynamic transformations are summarized in terms of endogenous driving momenta in relation to diseased microenvironment characteristics as well as external stimuli, and the limitations of current dynamic DDSs and challenges of future dynamic DDSs for clinical translation are further discussed. [Display omitted] Dynamic drug delivery systems (DDSs) have the ability of transforming their morphology and functionality in response to the biological microenvironments at the disease site and/or external stimuli, show spatio-temporally controllable drug delivery, and enhance the treatment efficacy. Due to the large surface area and modification flexibility, two-dimensional (2D) inorganic nanomaterials are being increasingly exploited for developing intelligent DDSs for biomedical applications. In this review, we summarize the engineering methodologies used to construct transformable 2D DDSs, including changing compositions, creating defects, and surface dot-coating with polymers, biomolecules, or nanodots. Then we present and discuss dynamic inorganic 2D DDSs whose transformation is driven by the diseased characteristics, such as pH gradient, redox, hypoxia, and enzyme in the tumor microenvironment as well as the external stimuli including light, magnetism, and ultrasound. Finally, the limitations and challenges of current transformable inorganic DDSs for clinical translation and their in vivo safety assessment are discussed. [ABSTRACT FROM AUTHOR]

Folate-functionalized polyoxometalate nanoparticles have unique oxidase-like activity, which can facilitate the fast oxidation of organic dyes without using any oxidizing agents or peroxidases especially at neutral pH conditions. This nanoparticle could be used as an agent in colorimetric multiplexed immunoassays. [ABSTRACT FROM AUTHOR]

A graphene oxide-based nano-metal composite oxide CuFe2O4/GO was successfully prepared by a versatile self-assembly approach. Structure and morphological characterization of CuFe2O4/GO nanocomposite were studied in detail by a series of characterization techniques including XRD, FT-IR, XPS, BET, SEM, and TEM. The results revealed that the self-assembly process did not destroy the composition and morphology of the spinel-structured CuFe2O4 particle, and the transparent GO sheets with wrinkled and rough texture are tightly coated on the surface of CuFe2O4 nanoparticles like a layer of thin gauze clothing. The particle size of CuFe2O4 is about 200 nm. Catalytic activity of as-prepared CuFe2O4/GO nanocomposite on the thermal decomposition of cyclotrimethylene trinitramine (RDX) was investigated via differential scanning calorimetry (DSC). The experimental results show that the CuFe2O4/GO nanocomposite has much higher catalytic activity than single CuFe2O4 nanoparticles and GO. Thermal decomposition temperature and apparent activation energy of RDX were reduced from 241.27 to 220.34 °C and from 172.6 to 142.56 kJ mol−1, respectively. The improved performance could be attributed to the "positive synergistic effect" between CuFe2O4 nanoparticles and GO. [ABSTRACT FROM AUTHOR]

Combination of kinds of therapy modalities is promising for effective cancer treatment. Herein, a kind of multifunctional nanoparticles (NPs) was developed for cancer chemo-photothermal therapy applications. Polypyrrole (PPy) NPs were formed using a facile polymerization method using poly(ethyleneimine) (PEI) as stabilizer, followed by polyethylene glycol (PEG) modification and anticancer drug doxorubicin (DOX) loading. Showing obvious absorbance in the NIR range, the obtained PPy-PEI-PEG NPs displayed well photothermal ability with desirable photothermal stability. The release of the loaded DOX can be promoted by pH and laser stimulation. Compared with single therapy modality, the combination of chemotherapy and photothermal therapy showed higher cancer cell killing effect. The cellular internalization of the obtained NPs was proved to be effective. The developed multifunctional NPs are promising candidates for combined therapy of cancer cells. [ABSTRACT FROM AUTHOR]

A self-cleaning transparent thin-film photovoltaic device composed of a perovskite LaAlO 3 nanoparticle modified Cu 2 O/CeO 2 nanoarray pn junction is prepared via an electrochemical sol–gel surface-plasma method. The fabricated Cu 2 O/LaAlO 3 /CeO 2 thin-film photovoltaic device exhibits a transmittance of ∼80–85 % in the visible-light regime (λ > 520 nm), photovoltaic enhancement of ∼2.6 × 103 (photovoltaic conversion efficiency of ∼1.37 %), stable output over five months of cycling, and decent hydrophobicity (contact angle of 93.54°). These characteristics are mainly attributed to the perovskite LaAlO 3 nanoparticles and surface plasma modification. The appropriate Fermi level and high quantum yield improves the carrier kinetic equilibrium, balancing the transparency and photovoltaic conversion efficiency (supported by the Density Functional Theory). Surface plasma modification further enhances the solar and carrier efficiencies, while producing decent self-cleaning performance. Additionally, the extra hole-related carriers produced by the Cu vacancies optimize the kinetic equilibrium and the orderly CeO 2 array interval releases interfacial stress, providing good structural stability. [ABSTRACT FROM AUTHOR]

Nickel-cobalt bimetals sulfide synergistic modified CdS nanorods with active facets are fabricated by a simple continuously hydrothermal method, there, CdS nanorods are preliminarily fabricated by the hydrothermal method, and then Ni–Co–S nanoparticles are deposited on the surface of CdS nanorods. Evaluated by the photocatalytic hydrogen production, the photocatalytic performance of CdS/Ni–Co–S (∼6.56 mmol/g∙h) exhibits an obvious enhancement of about ∼240 folds than typical CdS. The main reasons for the HER enhancement are ascribed to that, the active facets can promote the photo-generated electron aggregating at surface to increase the HER activities, Pt-like behavior Ni–Co–S can promote the photo-generated electrons transferring/diffusing into the water, the small size of CdS nanorods and Ni–Co–S nanoparticles can provide sufficient HER active sites and shorten the transferring route, which can be supported by the electrochemical measurements. Image 1 • High index facets can promote photo-electron aggregating to increase HER activity. • Pt-like Ni–Co–S can promote photo-electron diffusing into water quickly. • CdS nanorods and Ni–Co–S nanoparticles can provide sufficient HER active sites. [ABSTRACT FROM AUTHOR]

A composite containing self-assembled MoO 2 nanoparticles and functional carbon nanosheets was obtained via a facile and controllable strategy. Two-dimensional functional carbon nanosheets as matrices have close contact with MoO 2 nanoparticles, which assists in the improvement of electronic conductivity, provides efficient pathways and accelerates electron transfer. The carbon nanosheets have functional groups on the surface, which could serve as the nucleation sites for MoO 2. The MC-0.12 composite shows optimal specific capacitance (190.9 F g-1 at 1 A g-1) and excellent cycle stability between monomers and composites with different constituents. The assembled symmetrical coin cell supercapacitor using MC-0.12 possesses the maximum energy density of 10.3 Wh kg-1 at a power density of 378 W kg-1 and still maintains the energy density of 7.9 Wh kg-1 at 1682 W kg-1 with a larger potential window. The capacitance retention (92%) of the assembled device is maintained after 2000 cycles, showing outstanding cycle life. Therefore, the integration of self-assembled MoO 2 nanoparticles with 2D functional carbon nanosheets provides the composite superior electrochemical performance for supercapacitor applications. [ABSTRACT FROM AUTHOR]