Journal of Nanomaterials The latest articles from Hindawi Publishing Corporation © 2016 , Hindawi Publishing Corporation . All rights reserved. Study of the Performance of the Organic Extracts of Chenopodium ambrosioides for Ag Nanoparticle Synthesis Tue, 30 Aug 2016 15:52:13 +0000 There are many ways to obtain metal nanoparticles: biological, physical, and chemical ways and combinations of these approaches. Synthesis assisted with plant extracts has been widely documented. However, one issue that is under discussion refers to the metabolites responsible for reduction and stabilization that confine nanoparticle growth and prevent coalescence between nanoparticles in order to avoid agglomeration/precipitation. In this study, Ag nanoparticles were synthesized using organic extracts of Chenopodium ambrosioides with different polarities (hexane, dichloromethane, and methanol). Each extract was phytochemically characterized to identify the nature of the metabolites responsible for nanoparticle formation. With methanol extract, the compounds responsible for reducing and stabilizing silver nanoparticle were associated with the presence of phenolic compounds (flavonoids and tannins), while, with dichloromethane and hexane extracts, the responsible compounds were mainly terpenoids. Large part of the reducing activity of secondary metabolites in C. ambrosioides is closely related to compounds with antioxidant capacity, such as phenolic compounds (flavone glycoside and isorhamnetin), which are the main constituents of the methanol extracts. Otherwise, terpenoids (trans-diol, -terpineol, monoterpene hydroperoxides, and apiole) are the central metabolites present in dichloromethane and hexane extracts. Luis M. Carrillo-López, Ramón M. Soto-Hernández, Hilda A. Zavaleta-Mancera, and Alfredo R. Vilchis-Néstor Copyright © 2016 Luis M. Carrillo-López et al. All rights reserved. PEDOT:PSS-Containing Nanohydroxyapatite/Chitosan Conductive Bionanocomposite Scaffold: Fabrication and Evaluation Tue, 30 Aug 2016 12:36:26 +0000 Conductive poly(3,4-ethylenedioxythiophene)-poly(4-styrene sulfonate) (PEDOT:PSS) was incorporated into nanohydroxyapatite/chitosan (nHA/CS) composite scaffolds through a freezing and lyophilization technique. The bionanocomposite conductive scaffold was then characterized using several techniques. A scanning electron microscope image showed that the nHA and PEDOT:PSS were dispersed homogeneously in the chitosan matrix, which was also confirmed by energy-dispersive X-ray (EDX) analysis. The conductive properties were measured using a digital multimeter. The weight loss and water-uptake properties of the bionanocomposite scaffolds were studied in vitro. An in vitro cell cytotoxicity test was carried out using mouse fibroblast (L929) cells cultured onto the scaffolds. Using a freezing and lyophilization technique, it was possible to fabricate three-dimensional, highly porous, and interconnected PEDOT:PSS/nHA/CS scaffolds with good handling properties. The porosity was 74% and the scaffold’s conductivity was  μS. The surface roughness was increased with the incorporation of nHA and PEDOT:PSS into the CS scaffold. The compressive mechanical properties increased significantly with the incorporation of nHA but did not change significantly with the incorporation of PEDOT:PSS. The PEDOT:PSS-containing nHA/CS scaffold exhibited significantly higher cell attachment. The PEDOT:PSS/nHA/CS scaffold could be a potential bionanocomposite conductive scaffold for tissue engineering. Alireza Lari, Tao Sun, and Naznin Sultana Copyright © 2016 Alireza Lari et al. All rights reserved. Hydrothermal Synthesis, Characterization, and In Vitro Drug Adsorption Studies of Some Nano-BioMOFs Tue, 30 Aug 2016 08:34:36 +0000 Three new nano-bioMOFs (NBMOFs) (copper serinate, copper prolinate, and copper threoninate) have been hydrothermally synthesized and characterized by the scanning electron microscopy (SEM). Molecular masses of these nanomaterials have been obtained by mass spectrometric studies. Successful in vitro drug adsorption of rosuvastatin drug has been carried out in these three nanosized materials. The amount of rosuvastatin adsorbed in these materials and its slow release after intervals have been monitored by the high performance liquid chromatography (HPLC). TGA and PXRD spectra of all these materials in pure form and after rosuvastatin adsorption have also been recorded to elaborate the phenomenon of in vitro drug adsorption in these materials. Tabinda Sattar, Muhammad Athar, and Muhammad Najamul Haq Copyright © 2016 Tabinda Sattar et al. All rights reserved. Photocatalytic and Photoelectrochemical Water Splitting on TiO2 via Photosensitization Tue, 30 Aug 2016 08:22:01 +0000 The search for an alternative to replace conventional fuel has been going on for years due to the limited storage of fossil fuel and excess CO2 emission from the fuel. Using H2 as fuel has gained wide attention recently, as well as consequently splitting of water into hydrogen and oxygen. Seminal semiconductors such as TiO2 and ZnO have their position of CB and VB in alignment with water reduction and oxidation potential, respectively, but their wide bandgap allows them to absorb only UV light of the solar spectrum. Combining narrow bandgap semiconductors or other visible light active sensitizers with TiO2/ZnO is a facile route to exploit the visible light region of the solar spectrum. In this review, I make an attempt to summarize the various photosensitizers used in combination with TiO2 for water splitting with recent reports as examples. Saji Thomas Kochuveedu Copyright © 2016 Saji Thomas Kochuveedu. All rights reserved. Effect of O2/Ar Gas Flow Ratios on Properties of Cathodic Vacuum Arc Deposited ZnO Thin Films on Polyethylene Terephthalate Substrate Sun, 28 Aug 2016 14:08:58 +0000 Cathodic vacuum arc deposition (CVAD) can obtain a good quality thin film with a low growth temperature and a high deposition rate, thus matching the requirement of film deposition on flexible electronics. This paper reported the room-temperature deposition of zinc oxide (ZnO) thin films deposited by CVAD on polyethylene terephthalate (PET) substrate. Microstructure, optical, and electrical measurements of the deposited ZnO thin films were investigated with various O2/Ar gas flow ratios from 6 : 1 to 10 : 1. The films showed hexagonal wurtzite crystal structure. With increasing the O2/Ar gas flow ratios, the -axis (002) oriented intensity decreased. The crystal sizes were around 16.03 nm to 23.42 nm. The average transmittance values in the visible range of all deposited ZnO films were higher than 83% and the calculated band gaps from the absorption data were found to be around 3.1 to 3.2 eV. The resistivity had a minimum value in the 3.65 × 10−3 Ω·cm under the O2/Ar gas flow ratio of 8 : 1. The luminescence mechanisms of the deposited film were also investigated to understand the defect types of room-temperature grown ZnO films. Chien-Wei Huang, Ru-Yuan Yang, Cheng-Tang Pan, and Min-Hang Weng Copyright © 2016 Chien-Wei Huang et al. All rights reserved. Effect of Ammonium Chloride Solution on the Growth of Phosphorus Gypsum Whisker and Its Modification Sun, 28 Aug 2016 09:00:56 +0000 Phosphogypsum is the by-product of phosphate of fertilizer or phosphate which causes serious environmental pollution. In this work, a series of phosphogypsum whiskers were prepared using phosphogypsum as raw materials and NH4Cl as additive through the atmospheric water solution method. The results showed that the ammonium chloride solution has a great influence on phosphogypsum whiskers growth and the solubility. The best whisker aspect ratio of phosphogypsum was preferred in 1 mol/L NH4Cl solution, in which the solubility achieved 6.434 mg/mL and the aspect ratio reached 69.29. Besides, NH4Cl was found to have a modified effect on gypsum whiskers’ growth and it can be used to get mesh or dendritic whiskers. Shouwei Jian, Mengqi Sun, Guihai He, Zhenzhen Zhi, and Baoguo Ma Copyright © 2016 Shouwei Jian et al. All rights reserved. UV Treatment of the Stabilizing Shell for Improving the Photostability of Silver Nanoparticles Thu, 25 Aug 2016 16:29:08 +0000 Silver nanoparticles or nanoclusters are quite sensitive to light exposure. In particular, irradiation in the localized surface plasmon resonance (LSPR) region brings about a drastic modification of their optical properties due to growth and reshaping of the nanoparticles. In order to obtain luminescent colloids, small silver colloidal nanoparticles were prepared in chloroform using vinylpyrrolidone oligomers as capping agent and their luminescence properties were used to control their stability upon prolonged exposure to visible light. The polymeric shell around the metal clusters was hardened through photo-cross-linking by UV light. This process did not alter the morphology and the optical properties of the nanoparticles but greatly improved the particle photostability as confirmed also by confocal laser scanning microscopy measurements. The data clearly show that UV curing of the stabilizing layer could be a simple postsynthetic procedure to obtain materials with stable properties. Silvia Rinaldi, Luigi Tarpani, and Loredana Latterini Copyright © 2016 Silvia Rinaldi et al. All rights reserved. Effects of Functionalized Graphene Nanoplatelets on the Morphology and Properties of Phenolic Resins Thu, 25 Aug 2016 16:14:13 +0000 Graphene nanoplatelets (Gnps) were covalently functionalized by 3-aminopropyltriethoxysilane (KH550) and noncovalently functionalized by Triton X-100, respectively. The morphology and structure of KH550 modified graphene (K-Gnp) and Triton X-100 modified graphene (T-Gnp) were characterized by Fourier transform infrared spectroscopy, scanning electron micrograph, and Raman spectrometer. The influences of K-Gnp and T-Gnp on thermal conductivity, fracture toughness, and thermal stability of the boron phenolic resin (BPR) were investigated. Both covalently functionalized K-Gnp and noncovalently functionalized T-Gnp not only improve the dispersion of Gnp in the polymer matrix but also increase interfacial bonding strength between the BPR matrix and Gnp, thus leading to the enhanced mechanical property and thermal stability of nanocomposites. Besides this, mechanical property and thermal stability of the BPR containing K-Gnp are superior to those of BPR containing T-Gnp. Jing Dai, Chao Peng, Fuzhong Wang, Guangwu Zhang, and Zhixiong Huang Copyright © 2016 Jing Dai et al. All rights reserved. Preparation, Characterization, and In Vitro and Vivo Antitumor Activity of Oridonin-Conjugated Multiwalled Carbon Nanotubes Functionalized with Carboxylic Group Thu, 25 Aug 2016 11:54:47 +0000 Carbon nanotubes have shown great potential in tumor therapy. Oridonin (ORI) is a poorly water-soluble diterpenoid compound (C20H28O6) used in the treatment of esophageal and hepatic carcinoma for decades. For the purpose of enhancing the antitumor potency and reducing cytotoxicity of ORI, multiwalled carbon nanotubes functionalized with carboxylic group (MWCNTs-COOH) were used as ORI carrier. ORI was noncovalently encapsulated into (or onto) the functionalized carbon nanotubes (MWCNTs-ORI). The obtained MWCNTs-ORI has been characterized. The ORI loading efficiency in MWCNTs-COOH carrier was studied to be about 82.6% (w/w). In vitro cytotoxicity assay on MWCNTs-ORI gave IC50 of  μg/mL and ORI-F gave IC50 of  μg/mL. The antitumor effect studies in vivo showed that MWCNTs-ORI improved antitumor activity of ORI in comparison with ORI-F. The tumor inhibition ratio for MWCNTs-ORI ( g·Kg−1·d−1) was 86.4%, higher than that of ORI-F ( g·Kg−1·d−1) which was 39.2%. This can greatly improve the pharmaceutical efficiency and reduce potential side effects. Chuanjin Wang and Wei Li Copyright © 2016 Chuanjin Wang and Wei Li. All rights reserved. Preparation of Graphene/TiO2 Composite Nanomaterials and Its Photocatalytic Performance for the Degradation of 2,4-Dichlorophenoxyacetic Acid Thu, 25 Aug 2016 10:16:33 +0000 The graphene (GR) was prepared by an improved electrochemical stripping method using a high-purity graphite rod as raw material and high temperature heat reduction in hydrogen atmosphere, and the graphene/TiO2 (GR/TiO2) composite nanomaterials were manufactured by the method of sol-gel and high temperature crystallization in hydrogen atmosphere using butyl titanate and electrolysis graphene as precursors. The physical and chemical properties of the composites had been characterized by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-Vis spectrophotometer (UV-Vis), scanning electron microscopy (SEM), Transmission Electron Microscope (TEM),  and specific surface area (SSA) by BET method. The photocatalytic properties of GR/TiO2 composites nanomaterials in anoxic water were studied by using 2,4-dichlorophenoxyacetic acid (2,4-D) as probe. The results showed that graphite was well intercalated and peeled by a facile electrolysis method in different electric field environment; a well dispersed and rings structure of graphene was prepared by coupling ultrasound-assisted changing voltage electrochemical stripping technology. The as-prepared GR/TiO2 composites had good performance for the photocatalytic degradation of 2,4-D in anoxic water; the chlorines were removed from benzene ring; the middle products of dichlorophenol, chlorophenol, phloroglucinol, and so forth were produced from the photocatalytic redox reaction of 2,4-D in anoxic water; parts of 2,4-D were decomposed completely, and CO2 and H2O were produced. Donggen Huang, Tianzi Yang, Zhuanghong Mo, Qin Guo, Shuiqing Quan, Cui Luo, and Lei Liu Copyright © 2016 Donggen Huang et al. All rights reserved. A Flexible and Highly Sensitive Piezoresistive Pressure Sensor Based on Micropatterned Films Coated with Carbon Nanotubes Thu, 25 Aug 2016 07:03:43 +0000 Excellent flexibility, high sensitivity, and low consumption are essential characteristics in flexible microtube pressure sensing occasion, for example, implantable medical devices, industrial pipeline, and microfluidic chip. This paper reports a flexible, highly sensitive, and ultrathin piezoresistive pressure sensor for fluid pressure sensing, whose sensing element is micropatterned films with conductive carbon nanotube layer. The flexible pressure sensor, the thickness of which is 40 ± 10 μm, could be economically fabricated by using biocompatible polydimethylsiloxane (PDMS). Experimental results show that the flexible pressure sensor has high sensitivity (0.047 kPa−1 in gas sensing and 5.6 × 10−3 kPa−1 in liquid sensing) and low consumption (<180 μW), and the sensor could be used to measure the pressure in curved microtubes. Jia-lin Yao, Xing Yang, Na Shao, Hui Luo, Ting Zhang, and Wu-gui Jiang Copyright © 2016 Jia-lin Yao et al. All rights reserved. Thin Film Nanofibrous Composite Membrane for Dead-End Seawater Desalination Wed, 24 Aug 2016 15:10:54 +0000 The aim of the study was to prepare a thin film nanofibrous composite membrane utilized for nanofiltration technologies. The composite membrane consists of a three-layer system including a nonwoven part as the supporting material, a nanofibrous scaffold as the porous surface, and an active layer. The nonwoven part and the nanofibrous scaffold were laminated together to improve the mechanical properties of the complete membrane. Active layer formations were done successfully via interfacial polymerization. A filtration test was carried out using solutions of MgSO4, NaCl, Na2SO4, CaCl2, and real seawater using the dead-end filtration method. The results indicated that the piperazine-based membrane exhibited higher rejection of divalent salt ions (>98%) with high flux. In addition, the m-phenylenediamine-based membrane exhibited higher rejection of divalent and monovalent salt ions (>98% divalent and >96% monovalent) with reasonable flux. The desalination of real seawater results showed that thin film nanofibrous composite membranes were able to retain 98% of salt ions from highly saline seawater without showing any fouling. The electrospun nanofibrous materials proved to be an alternative functional supporting material instead of the polymeric phase-inverted support layer in liquid filtration. Baturalp Yalcinkaya, Fatma Yalcinkaya, and Jiri Chaloupek Copyright © 2016 Baturalp Yalcinkaya et al. All rights reserved. Chitosan-Alginate Nanoparticle System Efficiently Delivers Doxorubicin to MCF-7 Cells Wed, 24 Aug 2016 12:40:15 +0000 A chitosan-alginate nanoparticle system encapsulating doxorubicin (DOX) was prepared by a novel ionic gelation method using alginate as the crosslinker. These nanoparticles were around 100 nm in size and more stable with higher positive zeta potential and had higher % encapsulation efficiency (95%) than DOX loaded chitosan nanoparticles (DOX Csn NP) crosslinked with sodium tripolyphosphate (STPP). FTIR spectroscopy and thermogravimetric analysis revealed successful loading of DOX. In vitro drug release showed an initial release phase followed by slow release phase with higher cumulative release obtained with DOX loaded chitosan-alginate nanoparticles (DOX Csn-Alg NP). The in vitro cytotoxicity of DOX released from the two nanoparticle systems showed a notable difference on comparison with that of free DOX on the MCF-7 cell line. The SRB assay, AO/EB staining, and fluorescence uptake study indicated that free DOX only showed dose dependent cytotoxicity, whereas both dose and time dependency were exhibited by the two sets of NPs. While both systems show sustained release of DOX, from the cell viability plots, DOX Csn-Alg NPs showed their superiority over DOX Csn NPs. The results obtained are useful for developing DOX Csn-Alg NPs as a sustained release carrier system for DOX. Nuwanthi P. Katuwavila, A. D. L. Chandani Perera, Sameera R. Samarakoon, Preethi Soysa, Veranja Karunaratne, Gehan A. J. Amaratunga, and D. Nedra Karunaratne Copyright © 2016 Nuwanthi P. Katuwavila et al. All rights reserved. Study on NO Heterogeneous Reduction Mechanism under Gasification Condition Wed, 24 Aug 2016 09:18:27 +0000 Chemisorption of NO and successive heterogeneous reduction mechanisms on the well-defined char models under carbon/char-CO2 gasification condition were investigated using density functional theory at the B3LYP/6-31G (d) level of theory. The characteristics of gasification process were concluded and incorporated into the theoretical calculations by establishing three gasification char models and taking into account the presence of CO in ambient gas pool. The results indicate that both the configuration of char model and adsorption mode have significant influence on the NO adsorption energy. Intensive gasification surface is likely to be thermally unfavorable and the O-down mode is regarded as the most inactive approach for NO’s adsorbing. Finally, NO heterogeneous reduction mechanisms on the three char models under gasification are proposed based on detailed analysis on thermodynamic data and atomic bond populations. Xiangyong Huang, Chengbin Zhang, Xiaochuan Li, and Che Huang Copyright © 2016 Xiangyong Huang et al. All rights reserved. Comparison of Acid Red 114 Dye Adsorption by Fe3O4 and Fe3O4 Impregnated Rice Husk Ash Wed, 24 Aug 2016 08:19:37 +0000 The removal of Acid Red 114 (AR114) dye by adsorption process, using the magnetic nanoparticle (RHA-MNP) which is produced from rice husk ash burned at 300°C and the magnetic nanoparticle (MNP, Fe3O4), was studied. Batch processes were used under different test parameters: pH (2, 4, 6, and 10) and without pH, initial dye concentration (20, 40, 60, 80, and 100 mg/L), and contact time (0, 1, 5, 10, 15, 30, 45, 60, 90, and 150 min). Optimum conditions for AR114 removal were found to be at natural pH (pH without correction) for both adsorbents. Freundlich isotherm was found to be more consistent for MNP and Langmuir isotherm was found to be more consistent for RHA-MNP. The maximum adsorption capacities of MNP and RHA-MNP adsorbents for AR114 dye were equal to 111 mg/g. The kinetic experimental data fitted the pseudo-second-order model for both MNP and RHA-MNP. It can be concluded that RHA-MNP which is a waste could be used as low-cost adsorbent to remove AR114 from aqueous solution. Gul Kaykioglu and Elcin Gunes Copyright © 2016 Gul Kaykioglu and Elcin Gunes. All rights reserved. Advances in Electrospun Nanofibers Wed, 24 Aug 2016 06:47:08 +0000 Niranjan Patra, Miroslav Cernik, and Marco Salerno Copyright © 2016 Niranjan Patra et al. All rights reserved. Treatment of Bone Losses in Revision Total Hip and Knee Arthroplasty Using Trabecular Metal: Current Literature Tue, 23 Aug 2016 17:02:53 +0000 Revision Total Knee or Hip Arthroplasty is challenging procedures for surgeons usually characterized by bone loss. There are different options available to treat those bone losses. However, there is still a concern on the stability of bone-implant interface, which is mandatory to achieve good long-term results in prosthetic implants. Recently, porous tantalum has been introduced, with the aim of improving the bone-implant interface fixation and implant primary stability. Different solutions for the treatment of bone defects in both revision Total Knee and Hip Arthroplasty have been proposed. In revision Total Hip Arthroplasty (THA) tantalum shells can be used to treat Paprosky type III defects also, because of their mechanical properties. Similarly, trabecular metal has been proposed in revision Total Knee Arthroplasty (TKA), being considered a viable option to treat severe type 2 or 3 defects. The aim of this paper is to review the mechanical properties and characteristics of tantalum. Furthermore, we will discuss its role in treating bone defects in both revision THA and TKA, as well as the outcome reported in literature. Umberto Cottino, Federica Rosso, Federico Dettoni, Matteo Bruzzone, Davide Edoardo Bonasia, and Roberto Rossi Copyright © 2016 Umberto Cottino et al. All rights reserved. Preparation and Characterization of Vancomycin-Loaded Electrospun Rana chensinensis Skin Collagen/Poly(L-lactide) Nanofibers for Drug Delivery Thu, 18 Aug 2016 13:56:20 +0000 Collagen was extracted from abandoned Rana chensinensis skin in northeastern China via an acid enzymatic extraction method for the use of drug carriers. In this paper we demonstrated two different nanofiber-vancomycin (VCM) systems, that is, VCM blended nanofibers and core-shell nanofibers with VCM in the core. Rana chensinensis skin collagen (RCSC) and poly(L-lactide) (PLLA) (3 : 7) were blended in 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) at a concentration of 10% (g/mL) to fabricate coaxial and blend nanofibers, respectively. Coaxial and blend electrospun RCSC/PLLA nanofibers containing VCM (5 wt%) were evaluated for the local and temporal delivery of VCM. The nanofiber scaffolds were characterized by environmental scanning electron microscope (ESEM), transmission electron microscopy (TEM), Fourier transform infrared spectra (FTIR), differential scanning calorimeter (DSC), water contact angle (WCA), and mechanical tests. The drug release of VCM in these two systems was compared by using UV spectrophotometer. The empirical result indicated that both the blend and coaxial RCSC/PLLA scaffolds followed sustained control release for a period of 80 hours, but the coaxial nanofiber might be a potential drug delivery material for its better mechanical properties and sustained release effect. Mei Zhang, Ziqi Li, Lihua Liu, Zhouyang Sun, Wendi Ma, Zhichao Zhang, Rui Zhang, and Dahui Sun Copyright © 2016 Mei Zhang et al. All rights reserved. Penetration and Silencing Activity of VEGF Dicer Substrate siRNA Vectorized by Chitosan Nanoparticles in Monolayer Culture and a Solid Tumor Model In Vitro for Potential Application in Tumor Therapy Thu, 18 Aug 2016 13:47:26 +0000 Penetration and distribution of drug through the avascular regions of human solid tumors after extravasation are crucial concerns for antitumor efficacy. To address this issue, an in vitro solid tumor model of multicellular layers (MCLs) of human colorectal cancer cells (DLD-1) was established. In an attempt to deliver Dicer substrate small interfering RNA (DsiRNA), chitosan (CS) nanoparticles have been developed for targeting vascular endothelial growth factor (VEGF) gene for tumor growth inhibition. The DsiRNA-CS nanoparticles prepared by ionic gelation method had provided maximal protection of DsiRNA in full human serum up to 48 h incubation. RT-PCR studies revealed significant concentration- and time-dependent knock-down of VEGF mRNA and its product due to uniform penetration of DsiRNA-CS nanoparticles throughout MCLs. Taken together, this study also demonstrated that DsiRNA-CS nanoparticles could effectively knock down VEGF gene as therapeutic target in monolayer culture or in solid tumor model for potential treatment of human colorectal carcinoma. Maria Abdul Ghafoor Raja, Haliza Katas, and Zariyantey Abd Hamid Copyright © 2016 Maria Abdul Ghafoor Raja et al. All rights reserved. Nanoscale Biological Materials Thu, 18 Aug 2016 06:27:58 +0000 Kilho Eom, Serdal Kirmizialtin, Yaling Liu, and Zhiping Xu Copyright © 2016 Kilho Eom et al. All rights reserved. Electrical Properties of Polytypic Mg Doped GaAs Nanowires Wed, 17 Aug 2016 16:50:06 +0000 The electrical transport properties of individual Mg doped GaAs nanowires are investigated. It is shown that Mg can be successfully used as a nontoxic p-type dopant in GaAs nanowires. The doping levels, expanding over two orders of magnitude, and free holes mobility in the NW were obtained by the analysis of field effect transistors transfer curves. The temperature dependence of the electrical resistivity above room temperature shows that the polytypic structure of the NWs strongly modifies the NWs charge transport parameters, like the resistivity activation energy and holes mobility. At lower temperatures the NWs exhibit variable range hopping conduction. Both Mott and Efros-Shklovskii variable range hopping mechanisms were clearly identified in the nanowires. N. Cifuentes, E. R. Viana, H. Limborço, D. B. Roa, A. Abelenda, M. I. N. da Silva, M. V. B. Moreira, G. M. Ribeiro, A. G. de Oliveira, and J. C. González Copyright © 2016 N. Cifuentes et al. All rights reserved. Enhanced Structural, Thermal, and Electrical Properties of Multiwalled Carbon Nanotubes Hybridized with Silver Nanoparticles Wed, 17 Aug 2016 13:49:49 +0000 The objective of this study is to evaluate the structural, thermal, and electrical properties of multiwalled carbon nanotubes (MWNT) hybridized with silver nanoparticles (AgNP) obtained via chemical reduction of aqueous silver salt assisted with sodium dodecyl sulphate (SDS) as stabilizing agent. Transmission electron microscopy (TEM) reveals microstructural analysis of the MWNT-Ag hybrids. The Fourier transform infrared (FTIR) spectra prove the interactions between the AgNP and carboxyl groups of the MWNT. Raman spectra reveal that the D- to G-band intensity ratios and increase upon the deposition of AgNP onto the surface of the MWNT. Thermogravimetric analysis (TGA) shows that the MWNT-Ag hybrids decompose at a much faster rate and the weight loss decreased considerably due to the presence of AgNP. Nonlinearity of current-voltage () curves indicates that electrical transport of pristine MWNT is enhanced when AgNP is induced as charge carriers in the MWNT-Ag hybrids. The threshold voltage value for the MWNT doped with a maximum of 70 vol% of AgNP was substantially reduced by 65% relative to the pristine MWNT. The MWNT-Ag hybrids have a favourable electrical characteristic with a low threshold voltage that shows enhancement mode for field-effect transistor (FET) applications. Yusliza Yusof, Mohd Irwan Zaidi, and Mohd Rafie Johan Copyright © 2016 Yusliza Yusof et al. All rights reserved. 177Lu-Dendrimer Conjugated to Folate and Bombesin with Gold Nanoparticles in the Dendritic Cavity: A Potential Theranostic Radiopharmaceutical Tue, 16 Aug 2016 16:11:49 +0000 177Lu-labeled nanoparticles conjugated to biomolecules have been proposed as a new class of theranostic radiopharmaceuticals. The aim of this research was to synthesize 177Lu-dendrimer(PAMAM-G4)-folate-bombesin with gold nanoparticles (AuNPs) in the dendritic cavity and to evaluate the radiopharmaceutical potential for targeted radiotherapy and the simultaneous detection of folate receptors (FRs) and gastrin-releasing peptide receptors (GRPRs) overexpressed in breast cancer cells. p-SCN-Benzyl-DOTA was conjugated in aqueous-basic medium to the dendrimer. The carboxylate groups of Lys1Lys3(DOTA)-bombesin and folic acid were activated with HATU and also conjugated to the dendrimer. The conjugate was mixed with 1% HAuCl4 followed by the addition of NaBH4 and purified by ultrafiltration. Elemental analysis (EDS), particle size distribution (DLS), TEM analysis, UV-Vis, and infrared and fluorescence spectroscopies were performed. The conjugate was radiolabeled using 177LuCl3 or 68GaCl3 and analyzed by radio-HPLC. Studies confirmed the dendrimer functionalization with high radiochemical purity (>95%). Fluorescence results demonstrated that the presence of AuNPs in the dendritic cavity confers useful photophysical properties to the radiopharmaceutical for optical imaging. Preliminary binding studies in T47D breast cancer cells showed a specific cell uptake (%). 177Lu-dendrimer(AuNP)-folate-bombesin may be useful as an optical and nuclear imaging agent for breast tumors overexpressing GRPR and FRs, as well as for targeted radiotherapy. Héctor Mendoza-Nava, Guillermina Ferro-Flores, Flor de María Ramírez, Blanca Ocampo-García, Clara Santos-Cuevas, Liliana Aranda-Lara, Erika Azorín-Vega, Enrique Morales-Avila, and Keila Isaac-Olivé Copyright © 2016 Héctor Mendoza-Nava et al. All rights reserved. Thermal Properties of Silver Nanoparticle Sintering Bonding Paste for High-Power LED Packaging Tue, 16 Aug 2016 13:23:03 +0000 This paper describes the preparation of low-temperature sintered nanosilver paste with inverse microemulsion method with Span-80/Triton X-100 as the mixed-surfactant and analyzes the influence of different sintering parameters (temperature, pressure) on the shear properties of low-temperature sintering of nanosilver. Experimental results show that the shear strength of the low-temperature sintering of nanosilver increases as the temperature and pressure increase. But there are many pores and relative fewer cracks on the sintering layer after low-temperature sintered. The test thermal resistance of low-temperature sintered nanosilver paste is 0.795 K/W which is greater than SAC305 weld layer with a T3ster thermal analyzer. The adhesive performance and the heat dispersion of low-temperature sintered nanosilver paste need to be further researched and improved. Ping Zhang, Rongzhuan Wei, Jianhua Zeng, Miao Cai, Jing Xiao, and Daoguo Yang Copyright © 2016 Ping Zhang et al. All rights reserved. High Surface Area Ceria Nanoparticles via Hydrothermal Synthesis Experiment Design Tue, 16 Aug 2016 12:31:57 +0000 Hydrothermal synthesis of CeO2 was optimized on two reactant concentrations and synthesis temperature and duration, in order to achieve material having the greatest specific surface area (SSA). Taguchi method of experimental design was employed in evaluation of the relative importance of synthesis parameters. CeO2 nanoparticles were characterized using X-ray diffraction, nitrogen adsorption-desorption isotherms, and scanning electron microscopy. Optimum conditions for obtaining particles with greater SSA were calculated according to Taguchi’s model “the-higher-the-better.” Synthesis temperature was found to be the only parameter significant for enabling nanoparticles with greater SSA. Mesoporous nanocrystalline ceria with SSA as great as 226 m2 g−1 was achieved, which is unprecedented for the hydrothermally synthesized ceria. The reason for this achievement was found in temperature dependence of the diffusion coefficient which, when low, favors nucleation yielding with fine particles, while when high it favors crystal growth and formation of one-dimensional structures. The occurrence of 1D-structure in sample exhibiting the smallest SSA was confirmed. Very fine crystallites with crystallite size as low as 5.9 nm have been obtained being roughly inverse proportional to SSA. Selected samples were tested as catalyst for soot oxidation. Catalyst morphology turned out to be decisive factor for catalytic activity. Stanislav Kurajica, Iva Minga, Martina Guliš, Vilko Mandić, and Ivan Simčić Copyright © 2016 Stanislav Kurajica et al. All rights reserved. Nanoparticle-Mediated Photodynamic Therapy for Mixed Biofilms Tue, 16 Aug 2016 11:52:56 +0000 Wounds associated with diabetes are difficult to heal and often stay unhealed, leading to higher morbidity and mortality in the diabetic population. A major barrier to the successful healing of chronic diabetic wounds is the presence of biofilm-mediated infections. In recent years, photodynamic therapy (PDT) has emerged as a promising treatment modality for the management of chronic wounds. The objective of the present study was to evaluate the effectiveness of toluidine blue- (TB-) loaded nanoparticle-mediated PDT in eradicating antibiotic-resistant polymicrobial biofilms of Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus in an in vitro model. Dioctyl sodium sulfosuccinate (aerosol OT, AOT)-alginate nanoparticles with high TB loading (%) were formulated using a double emulsification cross-linking method. TB nanoparticles induced effective killing of planktonic P. aeruginosa (3.5 log10 CFU) and S. aureus (>5 log10 CFU) and their combined biofilms (2.8 log10 CFU for P. aeruginosa versus 3.4 log10 CFU for S. aureus). While P. aeruginosa biofilm was more resistant when compared to that of S. aureus, our results demonstrated effective eradication of complex biofilms of dual bacterial strains in vitro. Marina Usacheva, Buddhadev Layek, Saif S. Rahman Nirzhor, and Swayam Prabha Copyright © 2016 Marina Usacheva et al. All rights reserved. Impact of Substrate Outgassing on the Growth of Carbon Nanotubes Using the Single-Pulse Discharge Method Tue, 16 Aug 2016 09:58:49 +0000 Carbon nanotubes (CNTs) were fabricated in air using the electrical discharge machining method. The main parameters for this process were substrate temperature, peak current (), and pulse duration (τ). The substrate was baked at 50°C and this temperature was maintained for 12 h under vacuum chamber; it was then cooled to room temperature and stored in vacuum for outgassing. During single-pulse discharge in air, the substrate was heated from room temperature to the test temperatures (50 and 70°C). The results indicated that the length, density, and purity of CNTs grown on outgassed substrates were better than those of CNTs grown without outgassing. Additionally, CNTs grown with = 3 A and τ = 1200 μs were of better quality than those grown with other combinations of parameters. The size of the discharge pit was effectively reduced by 30% (80 μm). This finding may help in controlling the amount of peak current used during the process, thereby reducing the problems of heat-affected zones and electrode consumption. Consequently, there was substantial improvement in the zonal selectivity and reticular density of the CNTs grown using the single-pulse discharge method. C. H. Su and C. H. Huang Copyright © 2016 C. H. Su and C. H. Huang. All rights reserved. Biosynthesized Silver Nanoparticles Used in Preservative Solutions for Chrysanthemum cv. Puma Mon, 15 Aug 2016 09:52:43 +0000 The use of pulse solutions containing antimicrobials has been reported, but more research is necessary. To increase vase life and to study their effect on opening inflorescences, silver nanoparticles were used in vase solutions for cv. Puma Chrysanthemum stems. The nanoparticles were synthesized biologically using Chenopodium ambrosioides L. applied at concentrations of 0.01, 0.05, 0.1, 0.5, 1, and 5 mM and compared with a control. Treatments were replicated five times. The stems were cut to 50 cm and observed until the end of their vase life. Low concentrations of silver nanoparticles promoted inflorescence opening and leaf yellowing, while the control leaves remained green, but there was a lower degree of inflorescence opening. High concentrations of silver nanoparticles (0.5, 1, and 5 mM) caused senescence due to low water uptake through the stems. Statistical differences in inflorescence opening and diameter, bacterial growth (CFU mL−1) in vase solutions, fresh weight, water uptake, and vase life were found among treatments. Longer vase life and less weight loss were observed in the stems exposed to low concentrations of silver nanoparticles. Low concentrations of silver nanoparticles promoted inflorescence opening and increased vase life of Chrysanthemum cv. Puma. Luis M. Carrillo-López, Antonio Morgado-González, and Aurora Morgado-González Copyright © 2016 Luis M. Carrillo-López et al. All rights reserved. The High Photocatalytic Activity of SnO2 Nanoparticles Synthesized by Hydrothermal Method Mon, 15 Aug 2016 07:56:54 +0000 Tin oxide nanoparticles (SnO2 NPs) were prepared at low temperature by hydrothermal method. Synthesized SnO2 NPs were confirmed via characterization techniques such as UV-visible spectroscopy (UV-vis), X-ray diffraction (XRD), and Transmission Electron Microscope (TEM). The synthesized nanoparticles were in the size of 3 nm and they have high photocatalytic activity. The result showed that SnO2 NPs degraded 88.88% MB solution after 30 minutes of UV illumination and reached 90.0% for 120 minutes (2 hours) of UV illumination. Moreover, they degraded 79.26% MB solution after 90 minutes (1.5 hours) under assisted sunlight illumination. Pham Van Viet, Cao Minh Thi, and Le Van Hieu Copyright © 2016 Pham Van Viet et al. All rights reserved. Preparation of Highly Ordered Fiber Micropatterns by Assembly of Electrospun Nanofiber Segments Thu, 11 Aug 2016 16:16:30 +0000 A novel method for fabricating highly ordered fiber micropatterns by assembly of electrospun nanofiber segments was described. Polymethylglutarimide (PMGI) fiber segments with an average length of 3 µm were prepared by combining electrospinning with subsequent sonication treatment. Afterwards, the fiber segments dispersed in water were assembled on Norland optical adhesive (NOA) templates with different microstructural sizes and shapes, allowing formation of spatially uniform nanofibrous micropatterns on flat glass substrate. Regular fiber microarrays were produced when the feature size of NOA template was larger than 30 µm for square and strip geometry. In each microdot, the fiber segments had several layer thicknesses. This new method, which can prepare fiber micropatterns for different materials and microstructures, is suitable for functional device and cell biology applications. Jun Liu, Hua Wang, Meng-Jie Chang, and Hui-Ling Du Copyright © 2016 Jun Liu et al. All rights reserved.