Journal of Nanomaterials The latest articles from Hindawi © 2017 , Hindawi Limited . All rights reserved. Hydrogen Gas Sensing Using Palladium-Graphene Nanocomposite Material Based on Surface Acoustic Wave Thu, 25 May 2017 00:00:00 +0000 We report the fabrication and characterization of surface acoustic wave (SAW) hydrogen sensors using palladium-graphene (Pd-Gr) nanocomposite as sensing material. The Pd-Gr nanocomposite as sensing layer was deposited onto SAW delay line sensor-based interdigitated electrodes (IDTs)/aluminum nitride (AlN)/silicon (Si) structure. The Pd-Gr nanocomposite was synthesized by a chemical route and deposited onto SAW sensors by air-brush spraying. The SAW H2 sensor using Pd-Gr nanocomposite as a sensing layer shows a frequency shift of 25 kHz in 0.5% H2 concentration at room temperature with good repeatability and stability. Moreover, the sensor showed good linearity and fast response/recovery within ten seconds with various H2 concentrations from 0.25 to 1%. The specific interaction between graphene and SAW transfer inside AlN/Si structures yields a high sensitivity and fast response/recovery of SAW H2 sensor based on Pd-Gr/AlN/Si structure. Nguyen Hai Ha, Nguyen Hoang Nam, Dang Duc Dung, Nguyen Huy Phuong, Phan Duy Thach, and Hoang Si Hong Copyright © 2017 Nguyen Hai Ha et al. All rights reserved. Cell Growth Inhibition Effect of DsiRNA Vectorised by Pectin-Coated Chitosan-Graphene Oxide Nanocomposites as Potential Therapy for Colon Cancer Thu, 25 May 2017 00:00:00 +0000 Colonic-targeted drug delivery system is widely explored to combat colon-related diseases such as colon cancer. Dicer-substrate small interfering RNA (DsiRNA) has been explored for cancer therapy due to its potency in targeting specific gene of interest. However, its application is limited by rapid degradation and poor cellular uptake. To address this, chitosan-graphene oxide (CS-GO) nanocomposite was used to deliver DsiRNA effectively into cells. Additionally, pectin was used as compatibilization agent to allow specific delivery to the colon and protect the nanocomposites from the harsh environment in the stomach and small intestine. CS-GO-DsiRNA nanocomposites were prepared by electrostatic interaction between CS and GO prior to coating with pectin. The mean particle size of CS-GO-DsiRNA-pectin nanocomposites was  nm with PDI and zeta potential of and − mV, respectively. TEM analysis revealed smooth and spherical shape of CS-GO-DsiRNA nanocomposites and the shape became irregular after pectin coating. FTIR analysis further confirmed the successful formation of CS-GO-DsiRNA-pectin nanocomposites. Furthermore, the nanocomposites were able to entrap high amount of DsiRNA (% entrapment efficiency of %) with strong binding efficiency. CS-GO-DsiRNA-pectin nanocomposites also selectively inhibited cell growth of colon cancer cell line (Caco-2 cells) and were able to decrease VEGF level significantly. In a nutshell, pectin-coated DsiRNA-loaded CS-GO nanocomposites were successfully developed and they have a great potential to deliver DsiRNA to the colon effectively. Haliza Katas, Mohd Cairul Iqbal Mohd Amin, Nursyafiqah Moideen, Li Ying Ng, and Puteri Annisa Adhwa Megat Baharudin Copyright © 2017 Haliza Katas et al. All rights reserved. The Composition-Tunable Polydiacetylenic Complex Films: Conformational Change upon Thermal Stimulation and Preferential Interaction with Specific Small Molecules Wed, 24 May 2017 00:00:00 +0000 Polydiacetylenic complex films were prepared using 10,12-pentacosadiynoic acid (PCDA) and para-xylenediamine (pXDA) upon acid-base interactions. The thermochromatic reversibility of the complex films was modulated by changing the mixed molar ratio (3 : 1, 2 : 1, and 1 : 1) of the two molecules. The corresponding conformational changes of the complex films were studied by ex situ FTIR analysis upon thermal stimulation for the first time. In addition, the binding specificities of α-, β-, and γ-cyclodextrins (CDs) with the films were studied, where the α-CDs can induce stronger red fluorescent emission of the films. These fundamental results may be useful for platforms that use these polydiacetylenic complex films as optoelectronic devices or chemical/biological sensors. Chao Wang, Jin Hyuk Park, Songwen Tan, Chunzhi Cui, Jing-Yi Jin, and Dong June Ahn Copyright © 2017 Chao Wang et al. All rights reserved. The Effects of Heteroatom Adsorption on the Electronic Properties of Phosphorene Wed, 24 May 2017 00:00:00 +0000 A new 2D material, phosphorene, has several remarkable advantages; various superiorities make phosphorene a research hotspot. This paper provides comprehensive information about the structure and electronic and magnetic properties of phosphorene adsorbed with atoms, including alkali and alkaline-earth metal atoms, nonmetallic atoms, noble metal atoms, and transition-metal atoms. Phosphorene adsorbed with alkali and alkaline-earth metal atoms, such as Li and Na adatoms, becomes an n-type semiconductor, while phosphorene adsorbed with Be and Mg atoms becomes a p-type semiconductor. In view of nonmetallic adatoms (B, C, N, and O), the B adatom decorated phosphorene becomes metallic, the band gap of phosphorene adsorbed with C adatom decreases, and the phosphorene is p-type with N adatom, while the electronic property of O adatom adsorption case is affected slightly. Regarding noble metal adatoms adsorption condition, the Ag adatom makes phosphorene a n-type semiconductor, the Au adatom induces phosphorene to have a magnetism of 1 μB, and the electronic property of phosphorene is changed by adsorbing with Pt adatom. Among transition-metal adatoms, such as Fe, Ni, Co, Cu, and Zn adatoms, the band gap is reduced when Fe/Ni adatom adheres to the surface of phosphorene, The Co adsorbed phosphorene turns into a polar-gapless semiconductor and phosphorene is proved to be n-type with Cu adatom, but it is testified that the Zn atom is not suitable to adsorb on the phosphorene. Mengyao Sun, Zhiyong Wang, Yayun Zhao, Junchao Jin, Jianrong Xiao, and Liu Wang Copyright © 2017 Mengyao Sun et al. All rights reserved. Investigation of Various Cross-Linking Methods for the Immobilization of Cytosine Arabinoside on Bacterial Magnetosomes Mon, 22 May 2017 07:38:05 +0000 Bacterial magnetosomes (BMs) have emerged as potential drug delivery vehicles, possessing an iron oxide or iron sulfide core surrounded by a natural lipid membrane shell. In this study, we immobilized cytosine arabinoside (Ara-C) effectively on BMs by using various methods such as direct absorption (ABMs), and others include different cross-linkers such as genipin (GP) and glutaraldehyde (G). A well-dispersed Ara-C coupled bacterial magnetosomes resulted in significantly higher negative charge than that of naked BMs (− mV) confirming the drug loading. Out of all methods, direct absorption process led to the highest encapsulation efficiency and drug loading of % and %, respectively. These designs have shown the long-term drug release behavior without an initial burst release. Our results indicate that BMs-based nanoconjugates will potentially find widespread applications in pharmaceutical field. Qinglei Dai, Yiming Ma, Shibin Wang, Ranjith Kumar Kankala, and Yuangang Liu Copyright © 2017 Qinglei Dai et al. All rights reserved. Multiwalled Carbon Nanotubes Reinforced Polypropylene Composite Material Sun, 21 May 2017 06:05:31 +0000 Polypropylene (PP) composites reinforced with multiwalled carbon nanotubes (MWNTs) were prepared by using twin screw extruder. The experimental results showed that with the increasing amount of MWNTs the elongation at break decreased whereas the tensile strength, bending strength, and impact strength increased. By using scanning electron microscope (SEM), we find that the hydroxyl-modified carbon nanotube has better dispersion performance in PP and better mechanical properties. Juan Li Copyright © 2017 Juan Li. All rights reserved. Polymalic Acid Tritryptophan Copolymer Interacts with Lipid Membrane Resulting in Membrane Solubilization Sun, 21 May 2017 00:00:00 +0000 Anionic polymers with membrane permeation functionalities are highly desirable for secure cytoplasmic drug delivery. We have developed tritryptophan containing copolymer (P/WWW) of polymalic acid (PMLA) that permeates membranes by a mechanism different from previously described PMLA copolymers of trileucine (P/LLL) and leucine ethyl ester (P/LOEt) that use the “barrel stave” and “carpet” mechanism, respectively. The novel mechanism leads to solubilization of membranes by forming copolymer “belts” around planar membrane “packages.” The formation of such packages is supported by results obtained from studies including size-exclusion chromatography, confocal microscopy, and fluorescence energy transfer. According to this “belt” mechanism, it is hypothesized that P/WWW first attaches to the membrane surface. Subsequently the hydrophobic tryptophan side chains translocate into the periphery and insert into the lipid bilayer thereby cutting the membrane into packages. The reaction is driven by the high affinity between the tryptophan residues and lipid side chains resulting in a stable configuration. The formation of the membrane packages requires physical agitation suggesting that the success of the translocation depends on the fluidity of the membrane. It is emphasized that the “belt” mechanism could specifically function in the recognition of abnormal cells with high membrane fluidity and in response to hyperthermia. Hui Ding, Irving Fox, Rameshwar Patil, Anna Galstyan, Keith L. Black, Julia Y. Ljubimova, and Eggehard Holler Copyright © 2017 Hui Ding et al. All rights reserved. AgNPs and Ag/C225 Exert Anticancerous Effects via Cell Cycle Regulation and Cytotoxicity Enhancement Thu, 18 May 2017 07:23:30 +0000 Currently, cancer has become the leading cause of deaths and is a serious threat to human health. Nanotechnology-based medical applications are developing rapidly, especially in anticancer research, as nanomaterials can be retained in the cell after their entry across the cell membrane, making them potential candidates for application in the diagnosis and treatment of tumours. Here, we prepared silver nanoparticles (AgNPs) and silver/cetuximab (Ag/C225) particles of approximately 20 nm and investigated their inhibitory effect on proliferation of human nasopharyngeal carcinoma cell line CNE and laryngeal carcinoma cell line HEp-2. The MTT assay was used to determine their half-maximal inhibitory concentration (IC50) values. Electron microscopy revealed no obvious morphological differences between the prepared AgNPs and Ag/C225. Treatment of both cell lines with AgNPs and Ag/C225 increased the proportion of cells in the G0/G1 stage and decreased the proportion of cells in the S stage. AgNP and Ag/C225 treatments increased the expression of apoptotic proteins Bax and P21 and decreased the expression of Bcl-2 in CNE cells, compared to control cells. Ag/C225 is internalised by CNE cells, and it enhances X-irradiation-induced cytotoxicity. These results help increase the understanding of the anticancer effect of AgNPs and Ag/C225 and explore their application as radiosensitisers. Yan Zhang, Hong Lu, Dahai Yu, and Di Zhao Copyright © 2017 Yan Zhang et al. All rights reserved. C60 Filling Rate in Carbon Peapods: A Nonresonant Raman Spectra Analysis Thu, 18 May 2017 00:00:00 +0000 We calculated the nonresonant Raman spectra of peapods to determine the concentration of fullerenes inside single-walled carbon nanotubes. We focus on peapods with large diameters for which molecules can adopt a double helix configuration or a two-molecule layer configuration. Our calculations are performed within the framework of the bond-polarizability model combined with the spectral moment’s method. The changes in the Raman spectra as a function of filling rate and the configuration of molecules inside the nanotubes are identified and discussed. Our calculations support the experimental method proposed by Kuzmany to evaluate the concentration of molecules inside nanotubes. Fatima Fergani, Sidi Abdelmajid Ait Abdelkader, Hassane Chadli, Brahim Fakrach, Abdelhai Rahmani, Patrick Hermet, and Abdelali Rahmani Copyright © 2017 Fatima Fergani et al. All rights reserved. The Effects and Role of Polyvinylpyrrolidone on the Size and Phase Composition of Iron Oxide Nanoparticles Prepared by a Modified Sol-Gel Method Wed, 17 May 2017 00:00:00 +0000 Fe2O3 nanoparticles (as maghemite and hematite mixtures) were prepared using adapted sol-gel method from a polyvinylpyrrolidone (PVP) aqueous solution in various Fe3+ : PVP monomer ratios. Analysis of X-ray diffraction was obtained to evaluate the crystalline state, average crystallite size, and composition of iron oxide phases. The morphology and average nanoparticles size were evaluated by electronic transmission microscopy. Magnetic properties of iron oxide were analyzed at low and room temperatures. Optical characteristics were evaluated by UV-Vis photoacoustic spectroscopy and the Mössbauer spectrum was obtained in order to evaluate subtle changes in the nuclear environment of the iron atoms. Marcela F. Silva, Luiz A. S. de Oliveira, Mariani A. Ciciliati, Michele K. Lima, Flávio F. Ivashita, Daniela M. Fernandes de Oliveira, Ana Adelina W. Hechenleitner, and Edgardo A. G. Pineda Copyright © 2017 Marcela F. Silva et al. All rights reserved. Evaluation of Effective Elastic, Piezoelectric, and Dielectric Properties of SU8/ZnO Nanocomposite for Vertically Integrated Nanogenerators Using Finite Element Method Mon, 15 May 2017 08:30:12 +0000 A nanogenerator is a nanodevice which converts ambient mechanical energy into electrical energy. A piezoelectric nanocomposite, composed of vertical arrays of piezoelectric zinc oxide (ZnO) nanowires, encapsulated in a compliant polymeric matrix, is one of most common configurations of a nanogenerator. Knowledge of the effective elastic, piezoelectric, and dielectric material properties of the piezoelectric nanocomposite is critical in the design of a nanogenerator. In this work, the effective material properties of a unidirectional, unimodal, continuous piezoelectric composite, consisting of SU8 photoresist as matrix and vertical array of ZnO nanowires as reinforcement, are systematically evaluated using finite element method (FEM). The FEM simulations were carried out on cubic representative volume elements (RVEs). Four different types of arrangements of ZnO nanowires and three sizes of RVEs have been considered. The volume fraction of ZnO nanowires is varied from 0 to a maximum of 0.7. Homogeneous displacement and electric potential are prescribed as boundary conditions. The material properties are evaluated as functions of reinforcement volume fraction. The values obtained through FEM simulations are compared with the results obtained via the Eshelby-Mori-Tanaka micromechanics. The results demonstrate the significant effects of ZnO arrangement, ZnO volume fraction, and size of RVE on the material properties. Neelam Mishra, Braj Krishna, Randhir Singh, and Kaushik Das Copyright © 2017 Neelam Mishra et al. All rights reserved. Preparation of Cerium Dioxide Layers on Titanium by Electrodeposition with Organic Solution Mon, 15 May 2017 00:00:00 +0000 Layers of cerium dioxide nanoparticles were prepared on titanium by electrodeposition with organic solution. Three concentrations of cerium ions were used at 31.6 V. The organic solution was isobutanol and titanium foils were used as anodes and cathodes. Currents were monitored during the electrodeposition. Deposition times ranged from 0.5 to 8 h. Deposited Deposited layers were calcined at 700 K for 30 min. The morphology and composition of the deposited layers were examined by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). As-prepared and calcined deposition layers were assayed to be cerium dioxide. The average crystallite size increased from 4 to 7 nm through calcination at 700 K. Sizes of calcined cerium oxide agglomerates were ranging from 73 to 146 nm for 30 min deposition and 209 to 262 nm for 8 h deposition. The electrodeposition efficiencies of 0.5 h deposition at three concentrations were measured to be highest. Vaijayanti Namdeo Nande, Diana Kostyukova, Jeonghee Choi, and Yong Hee Chung Copyright © 2017 Vaijayanti Namdeo Nande et al. All rights reserved. Facile Synthesis of Solid Solution Microspheres through Ultrasonic Spray Pyrolysis for Improved Photocatalytic Activity Sun, 14 May 2017 08:20:32 +0000 Nanocrystal solid solutions were successfully prepared using a facile and reproducible method of ultrasonic spray pyrolysis with Cd(Ac)2·2H2O, ZnCl2, and thiourea as precursors. Scanning electron microscopy and transmission electron microscopy images show that the prepared particles possess microspherical morphology. The band gaps of the solid solutions can be tuned by changing the constituent stoichiometries of Cd and Zn. The X-ray diffraction peaks gradually shift to small angle, and the absorption edge shifts to long wavelength with increasing Cd molar fraction in the solid solution. The sample prepared at the Cd/Zn ratio of 1 : 1 displays the optimal activity by using the photocatalytic degradation of methyl orange in the aqueous solution as model reactions under visible light irradiation. This study provides an effective route to prepare spherical ternary photocatalysts with mesoporous structure for further investigations and practical applications. Jianhui Huang, Wenting Lin, Liyan Xie, and Wingkei Ho Copyright © 2017 Jianhui Huang et al. All rights reserved. Corrigendum to “The Effect of PEI and PVP-Stabilized Gold Nanoparticles on Equine Platelets Activation: Potential Application in Equine Regenerative Medicine” Thu, 11 May 2017 00:00:00 +0000 Mateusz Hecold, Roma Buczkowska, Aleksandra Mucha, Jakub Grzesiak, Olga Rac-Rumijowska, Helena Teterycz, and Krzysztof Marycz Copyright © 2017 Mateusz Hecold et al. All rights reserved. Effect of Precursor Concentration on Structural Optical and Electrical Properties of NiO Thin Films Prepared by Spray Pyrolysis Wed, 10 May 2017 07:29:14 +0000 Undoped nickel oxide (NiO) thin films were deposited on 500°C heated glass substrates using spray pyrolysis method at (0.015–0.1 M) range of precursor. The latter was obtained by decomposition of nickel nitrate hexahydrate in double distilled water. Effect of precursor concentration on structural, optical, and electrical properties of NiO thin films was investigated. X-ray diffraction (XRD) shows the formation of NiO under cubic structure with single diffraction peak along (111) plane at . When precursor concentration reaches 0.1 M, an increment in NiO crystallite size over 37.04 nm was obtained indicating the product nano structure. SEM images reveal that beyond 0.04 M as precursor concentration the substrate becomes completely covered with NiO and thin films exhibit formation of nano agglomerations at the top of the sample surface. Ni-O bonds vibrations modes in the product of films were confirmed by FT-IR analysis. Transparency of the films ranged from 57 to 88% and band gap energy of the films decreases from 3.68 to 3.60 eV with increasing precursor concentration. Electrical properties of the elaborated NiO thin films were correlated to the precursor concentration. Rafia Barir, Boubaker Benhaoua, Soufiane Benhamida, Achour Rahal, Toufik Sahraoui, and Rachid Gheriani Copyright © 2017 Rafia Barir et al. All rights reserved. Nanoferrofluid Materials: Advanced Structure Monitoring Using Optical Transmission in a Magnetic Field Wed, 10 May 2017 00:00:00 +0000 The optical transmission of a thin ferrofluid layer was investigated at various optical radiation wavelengths. The turning on of the durable external magnetic field pulse leads to nonmonotonic changes of the optical transmission value with minimal value during the field pulse. This phenomenon is related to the formation of columnar nanoparticle aggregates and transformation in the ferrofluid bulk. It was shown that time interval corresponding to the optical transmission minimum is proportional to the laser wavelength, which can be explained with Mie-like optical extinction on the ferrofluid aggregates and its dependence on the diameters of columnar aggregates. Hence, a simple experimental approach was proposed to measure and control the ferrofluid aggregates diameters in submicron spatial dimension ranges. Particularly, this approach could be used for the formation of composite nanomaterials consisting of polymers and magnetic nanoparticles with controlled structural parameters. These materials could be reused after parameters changes (e.g., lattice constant, aggregate size, and magnetic permeability tensor) with a heating/cooling cycle without the need for preparation of a new material from scratch. Serhii Shulyma, Bogdan Tanygin, Valery Kovalenko, and Michail Petrychuk Copyright © 2017 Serhii Shulyma et al. All rights reserved. Visible Light Excited Catalysis and Reusability Performances of TiO2@Pr:Y2SiO5 Upconversion Materials Tue, 09 May 2017 08:58:57 +0000 To get high efficiency photodegradation on pollutants under visible light, Pr(III) doped Y2SiO5 upconversion materials and anatase TiO2 nanofilm coated Pr:Y2SiO5 composite have been prepared by using a sol-gel method. XRD and SEM test results indicated that TiO2 nanofilm was well coated on Pr:Y2SiO5 to form TiO2@Pr:Y2SiO5 composite particles with the sizes of 0.5–1.0 μm. To avoid secondary pollution resulting from incomplete recovery of catalyst particles, TiO2@Pr:Y2SiO5 was loaded on the glass fiber filters by using a dip-coating method. It is found that the catalyst particles were embedded into the carrier firmly, even after having been reused for 6 times. The luminescence intensities of TiO2@Pr:Y2SiO5 were getting down sharply with the coating contents of TiO2 increased, which was attributed to the adsorption of the luminescence by the TiO2 film in situ. As a result, TiO2@Pr:Y2SiO5 with 4% TiO2, which presented lowest luminescence intensity, showed the highest efficiency on the photodegradation of nitrobenzene wastewater. The catalysts loaded on glass fiber filters showed excellent reusability on the photodegradation of nitrobenzene and presented a photodegradation rate of 95% at the first time and up to 75.9% even after 6 times of reusing by the treatment time of 12 h. Yan Jiao, Yamiao Wang, Min Li, Ying Liu, Ping Mao, and Yi Yang Copyright © 2017 Yan Jiao et al. All rights reserved. Structure and Morphology Effects on the Optical Properties of Bimetallic Nanoparticle Films Laser Deposited on a Glass Substrate Tue, 09 May 2017 08:27:54 +0000 Moving nanosecond laser system is used for laser-assisted thermodiffusion deposition of metallic nanoparticles from water-based colloidal solutions. The results obtained for both gold and silver nanoparticles show that film morphology strongly depends on laser scanning speed and the number of passages. We show, furthermore, the possibility of producing bimetallic Au:Ag thin films by laser irradiation of the mixed solutions. As a result of several laser scans, granular nanometric films are found to grow with a well-controlled composition, thickness, and morphology. By changing laser scanning parameters, film morphology can be varied from island structures to quasi-periodic arrays. The optical properties of the deposited structures are found to depend on the film composition, thickness, and mean separation between the particles. The transparency spectra of the deposited films are shown to be defined by their morphology. A. O. Kucherik, S. M. Arakelyan, S. V. Kutrovskaya, A. V. Osipov, A. V. Istratov, T. A. Vartanyan, and T. E. Itina Copyright © 2017 A. O. Kucherik et al. All rights reserved. Comprehensive Study of Ni Nanotubes for Bioapplications: From Synthesis to Payloads Attaching Sun, 07 May 2017 07:08:19 +0000 Due to the Ni nanotubes’ shape anisotropy, low specific density, large specific surface, and uniform magnetic field, they have been offered as carriers for targeted delivery of drug or protein and the process of their formation from synthesis stage to the stage of surface modification and protein attaching has been demonstrated. Some steps to hasten their biomedical application have been applied. First, to have full control over the carrier dimensions and structure parameters, electrodeposition method in pores of polyethylene terephthalate template has been applied. Second, to understand the scope of Ni nanostructures application, their degradation in media with different acidity has been studied. Third, to improve the biocompatibility and to make payloads attachment possible, nanotubes surface modification with organosilicon compound has been carried out. At last, the scheme of protein attaching to the nanostructure surface has been developed and the binding process was demonstrated as an example of the bovine serum albumin. A. L. Kozlovskiy, I. V. Korolkov, G. Kalkabay, M. A. Ibragimova, A. D. Ibrayeva, M. V. Zdorovets, V. S. Mikulich, D. V. Yakimchuk, A. E. Shumskaya, and E. Yu. Kaniukov Copyright © 2017 A. L. Kozlovskiy et al. All rights reserved. Dielectric and Electrical Properties of WS2 Nanotubes/Epoxy Composites and Their Use for Stress Monitoring of Structures Thu, 04 May 2017 00:00:00 +0000 The dielectric and electrical characteristics of the semiconductive WS2 nanotubes/epoxy composites were studied as a function of the nanotubes concentration and the pressure applied during their molding. In addition, the ability of WS2 nanotubes to serve as stress sensors in epoxy based nanocomposites, for health-monitoring applications, was studied. The nanocomposite elements were loaded in three-point bending configuration. The direct current was monitored simultaneously with stress-strain measurements. It was found that, in nanocomposites, above the percolation concentrations of the nanotubes, the electrical conductivity increases considerably with the applied load and hence WS2 nanotubes can be potentially used as sensors for health monitoring of structural components. A. Sedova, S. Khodorov, D. Ehre, B. Achrai, H. D. Wagner, R. Tenne, H. Dodiuk, and S. Kenig Copyright © 2017 A. Sedova et al. All rights reserved. Preparation and Characterization of a Tumor-Targeting Dual-Image System Based on Iron Oxide Nanoparticles Functionalized with Folic Acid and Rhodamine Sun, 30 Apr 2017 09:23:41 +0000 Cancer is one of the diseases with most deaths worldwide, around 8.2 million annually. For this reason, several treatments and diagnostic tools have been investigated and developed over the past decades. Among them, a dual-image system has been developed to achieve and enhance the detection of cancer, which has not been done with systems currently available. The present study describes the preparation of a dual-image targeting system composed of magnetic iron oxide nanoparticles functionalized with folic acid and rhodamine; nanoparticles synthesis was achieved by a coprecipitation method; the functionalization was carried out by a carbodiimide with folic acid and/or the rhodamine isothiocyanate; conjugates were characterized by spectrometric techniques; toxicity was measured by cell proliferation assay on HeLa cells using progressive concentrations of functionalized nanoparticles. Cellular uptake assay was carried out by competitive assay on HeLa cells. Iron oxide magnetite nanoparticles, modified with folic acid and rhodamine, were successfully synthetized with a particle size lower than 20 nm (TEM), EDS, HRTEM, and XDR showed highly crystalline Fe3O4 nanoparticles. Folic acid and rhodamine were conjugated with high efficiency. A significant selectivity and uptake, facilitated by surface modification of iron oxide nanoparticles with folic acid, were demonstrated. The multifunctional system showed suitable physicochemical and biological properties for cell targeting through folate receptors. Alejandra Ancira-Cortez, Enrique Morales-Avila, Blanca E. Ocampo-García, Carlos González-Romero, Luis A. Medina, Gustavo López-Téllez, and Erick Cuevas-Yáñez Copyright © 2017 Alejandra Ancira-Cortez et al. All rights reserved. Comparative Study of Structural, Electrical, and Magnetic Behaviour of Ni-Cu-Zn Nanoferrites Sintered by Microwave and Conventional Techniques Sun, 30 Apr 2017 07:21:43 +0000 spinel type ferrite nanoparticles have been synthesized by citrate precursor method. These nanoparticles were then given heat treatment using microwave and conventional sintering techniques. Various characterizations using X-ray powder diffraction (XRD), scanning electron microscope (SEM), LCR meter, and B-H loop tracer were carried out on the sintered specimens. The XRD spectra of these ferrites confirmed the formation of spinel structure. The average crystallite size calculated using Scherrer’s formula was found to be in the nanometer range, its value varying from 33 nm to 39 nm. Microwave sintered samples exhibited superior electrical and magnetic behaviour over their conventionally sintered counterparts. Feasibility of low temperature synthesis and promising properties will render these ferrites suitable for multilayer chip inductor applications. Biju Thangjam and Ibetombi Soibam Copyright © 2017 Biju Thangjam and Ibetombi Soibam. All rights reserved. Multiscale Characterization of Nanoengineered Fiber-Reinforced Composites: Effect of Carbon Nanotubes on the Out-of-Plane Mechanical Behavior Sun, 30 Apr 2017 00:00:00 +0000 The mechanical properties of the matrix and the fiber/matrix interface have a relevant influence over the mechanical properties of a composite. In this work, a glass fiber-reinforced composite is manufactured using a carbon nanotubes (CNTs) doped epoxy matrix. The influence of the CNTs on the material mechanical behavior is evaluated on the resin, on the fiber/matrix interface, and on the composite. On resin, the incorporation of CNTs increased the hardness by 6% and decreased the fracture toughness by 17%. On the fiber/matrix interface, the interfacial shear strength (IFSS) increased by 22% for the nanoengineered composite (nFRC). The influence of the CNTs on the composite behavior was evaluated by through-thickness compression, short beam flexural, and intraply fracture tests. The compressive strength increased by 6% for the nFRC, attributed to the rise of the matrix hardness and the fiber/matrix IFSS. In contrast, the interlaminar shear strength (ILSS) obtained from the short beam tests was reduced by 8% for the nFRC; this is attributed to the detriment of the matrix fracture toughness. The intraply fracture test showed no significant influence of the CNTs on the fracture energy; however, the failure mode changed from brittle to ductile in the presence of the CNTs. Carlos Medina, Eduardo Fernandez, Alexis Salas, Fernando Naya, Jon Molina-Aldereguía, Manuel F. Melendrez, and Paulo Flores Copyright © 2017 Carlos Medina et al. All rights reserved. Andiroba Oil (Carapa guianensis Aublet) Nanoemulsions: Development and Assessment of Cytotoxicity, Genotoxicity, and Hematotoxicity Thu, 27 Apr 2017 00:00:00 +0000 Andiroba oil (AO) is obtained from an Amazonian plant and is used in traditional medicine. We carried out a comparative study to test the cytotoxicity, genotoxicity, and hematotoxicity of the oil and its nanoemulsion (AN) in vitro (fibroblasts, lineage NIH/3T3) and in vivo (Swiss mice). The AN was characterized by DLS/Zeta, and its stability was investigated for 120 days. The biological activity of AN was assessed in vitro by MTT test and cell morphology analyses and in vivo by micronucleus, comet, and hematotoxicity tests. The AN presented a hydrodynamic diameter (Hd) of and PDI of and good stability at room temperature. The MTT test evidenced the cytotoxicity of AO and of AN only at their highest concentrations, but AN showed lower cytotoxicity than AO. A lower cytotoxicity of AN, when compared to AO, is in fact an interesting data suggesting that during therapeutic application there will be a lower impact in the cell viability of healthy cells. Cytotoxicity, genotoxicity, and hematotoxicity were not observed in vivo. These tests on the biological and toxicological effects of andiroba oil and nanostructured oil are still initial ones but will give a direction to future application in cosmetics and/or the development of new phytotherapics. Susana Suely Rodrigues Milhomem-Paixão, Maria Luiza Fascineli, Luis Alexandre Muehlmann, Karina Motta Melo, Hugo Leonardo Crisóstomo Salgado, Graziella Anselmo Joanitti, Julio Cesar Pieczarka, Ricardo Bentes Azevedo, Alberdan Silva Santos, and Cesar Koppe Grisolia Copyright © 2017 Susana Suely Rodrigues Milhomem-Paixão et al. All rights reserved. Commercial Gold Nanoparticles on Untreated Aluminum Foil: Versatile, Sensitive, and Cost-Effective SERS Substrate Thu, 27 Apr 2017 00:00:00 +0000 We introduce low-cost, tunable, hybrid SERS substrate of commercial gold nanoparticles on untreated aluminum foil (AuNPs@AlF). Two or three AuNP centrifugation/resuspension cycles are proven to be critical in the assay preparation. The limits of detection (LODs) for 4-nitrobenzenethiol (NBT) and crystal violet (CV) on this substrate are about 0.12 nM and 0.19 nM, respectively, while maximum analytical SERS enhancement factors (AEFs) are about 107. In comparative assays LODs for CV measured on AuNPs@Au film and AuNPs@glass are about 0.35 nM and 2 nM, respectively. The LOD for melamine detected on AuNPs@ Al foil is 27 ppb with 3 orders of magnitude for linear response range. Overall, AuNPs@AlF demonstrated competitive performance in comparison with AuNPs@ Au film substrate in SERS detection of CV, NBT, and melamine. To check the versatility of the AuNPs@AlF substrate we also detected KNO3 with LODs of 0.7 mM and SERS EF around 2 × 103, which is on the same order with SERS EF reported for this compound in the literature. Kristina Gudun, Zarina Elemessova, Laura Khamkhash, Ekaterina Ralchenko, and Rostislav Bukasov Copyright © 2017 Kristina Gudun et al. All rights reserved. Spawns Structure of Rod-Like ZnO Wrapped in Cellulose Nanofibers for Electromagnetic Wave Absorption Thu, 27 Apr 2017 00:00:00 +0000 Spawns structure of rod-like ZnO wrapped in the cellulose nanofibers was successfully fabricated through a facile one-step hydrothermal method, and their electromagnetic wave absorption properties were investigated. The structure and properties of the composite aerogel were characterized. The enlarged morphology images showed that the as-prepared cellulose nanofiber/ZnO samples were spawns structure of rod-like ZnO wrapped in the cellulose nanofibers. The composite aerogel in a wax matrix exhibited excellent electromagnetic wave absorption performance over 2–18 GHz. The widest absorption bandwidth of 30 wt% contained with reflection loss values less than −10 dB was up to 12 GHz (6–18 GHz) at the thickness of 5.5 mm and the minimum reflection loss value reached −26.32 dB at 15.2 GHz when the thickness of the absorber was 3 mm. Bitao Fan, Qiufang Yao, Chao Wang, Ye Xiong, Qingfeng Sun, and Chunde Jin Copyright © 2017 Bitao Fan et al. All rights reserved. Heterogeneous Responses of Ovarian Cancer Cells to Silver Nanoparticles as a Single Agent and in Combination with Cisplatin Wed, 26 Apr 2017 09:52:26 +0000 We investigated the effects of silver nanoparticle (AgNP) exposure in three ovarian cancer cell lines (A2780, SKOV3, and OVCAR3). We found that AgNPs were highly cytotoxic toward A2780 and SKOV3 cells but OVCAR3 cells were less sensitive to AgNPs. In agreement with the cytotoxicity data, AgNPs caused DNA damage in A2780 and SKOV3 cells, but not in OVCAR3 cells. A2780 and SKOV3 showed higher levels of basal reactive oxygen species (ROS) relative to OVCAR3 cells. AgNP exposure increased ROS levels in both A2780 and SKOV3 cells, but not in OVCAR3 cells. We found that the heterogeneous cytotoxicity was specific to the uptake of intact particles and was not due to differences in sensitivity to silver ions. Furthermore, the combination of AgNPs and standard-of-care platinum therapy, cisplatin (cis-diamminedichloroplatinum(II), CDDP), was synergistic for treatment of A2780 and OVCAR3 cells and the combination of AgNPs and CDDP showed a favorable dose reduction in all cell lines tested. These results provide insight into potential applications of AgNPs for treatment of ovarian cancer. Cale D. Fahrenholtz, Jessica Swanner, Maria Ramirez-Perez, and Ravi N. Singh Copyright © 2017 Cale D. Fahrenholtz et al. All rights reserved. Development of Paper Biosensor for the Detection of Phenol from Industrial Effluents Using Bioconjugate of Tyr-AuNps Mediated by Novel Isolate Streptomyces tuirus DBZ39 Wed, 26 Apr 2017 00:00:00 +0000 Paper biosensor was developed using Tyr-AuNps bioconjugate produced by Streptomyces for the detection of phenol from the effluent of wine, paper, and plastic industries. Among three filter papers assessed, Whatman number 2 filter paper was proved to be the best paper base for the development of biosensor. Tyrosinase and gold nanoparticles being produced by a single novel isolate Streptomyces tuirus DBZ39 proved to be efficient bioconjugate for the detection of phenol constituents, due to its biocompatibility. The substrate specific catalytic activity of the tyrosinase and unique Surface Plasmon Resonance attribute of gold nanoparticles are the cause for efficient detection of phenol constituents from the effluent of wine, paper, and plastic industries in 3 min. The different types and quantity of phenolic constituents in various industrial effluents, such as phenol in wine, dopamine in paper, and catechol in plastic effluents, were accurately detected by the bioconjugate. The efficacy of tyrosinase in the detection of phenol constituents was expected to be enhanced by the gold nanoparticles because of their electron, optical, and magnetic properties. This novel paper strip biosensor could be cost-effective and efficient means of future devices for the detection of phenolic pollutants from any environmental samples. Bi Bi Zainab Mazhari, Dayanand Agsar, and M. V. N. Ambika Prasad Copyright © 2017 Bi Bi Zainab Mazhari et al. All rights reserved. Growth of Carbon Nanofibers in Phenolic Resin for Carbon-Contained Refractory Using Different Catalysts Wed, 26 Apr 2017 00:00:00 +0000 Various phenolic resins modified with carbon nanofibers were prepared using Fe(NO3)3, Co(NO3)2, and Ni(NO3)3 as catalyst, respectively. The influences of different catalysts on the phase, microstructure evolution, and oxidation resistance of the modified phenolic resin were investigated by X-ray diffraction analysis, field-emission scanning electron microscopy, and thermal gravimetric analysis. The results showed that, compared with a single catalyst, the mixed catalysts (Co(NO3)2 : Fe(NO3)3 = 1 : 1) promoted the growth of the carbon nanofibers, which have the higher crystallinity, homogeneous dispersion, and nonagglomeration. These carbon nanofibers can effectively reduce carbon losses, increase char yield, and fill the holes in the thermal cracking process of phenolic resins. Jun Yu, Huizhong Zhao, Han Zhang, Jingjie Li, and Xiongfeng Ding Copyright © 2017 Jun Yu et al. All rights reserved. Peptide Self-Assembled Nanostructures for Drug Delivery Applications Mon, 24 Apr 2017 06:13:25 +0000 Peptide self-assembled nanostructures are very popular in many biomedical applications. Drug delivery is one of the most promising applications among them. The tremendous advantages for peptide self-assembled nanostructures include good biocompatibility, low cost, tunable bioactivity, high drug loading capacities, chemical diversity, specific targeting, and stimuli responsive drug delivery at disease sites. Peptide self-assembled nanostructures such as nanoparticles, nanotubes, nanofibers, and hydrogels have been investigated by many researchers for drug delivery applications. In this review, the underlying mechanisms for the self-assembled nanostructures based on peptides with different types and structures are introduced and discussed. Peptide self-assembled nanostructures associated promising drug delivery applications such as anticancer drug and gene drug delivery are highlighted. Furthermore, peptide self-assembled nanostructures for targeted and stimuli responsive drug delivery applications are also reviewed and discussed. Taotao Fan, Xiaoyan Yu, Bing Shen, and Leming Sun Copyright © 2017 Taotao Fan et al. All rights reserved.