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Results in Journal Soft Nanoscience Letters: 101

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Pratima Parashar Pandey
Soft Nanoscience Letters, Volume 10, pp 1-15; doi:10.4236/snl.2020.101001

Abstract:
The polymer nanocomposites have been the exponentially growing field of research for developing the materials in last few decades. The remarkable improvement in the polymer nanocomposite is found when a small amount of nanosized particles are added to a polymer matrix. The addition of inorganic solid nanoparticles (typically in the form of fibres, flakes, spheres or fine particles) into polymer matrix increases their physical, structural and mechanical properties. Since the polymer-nano composites have been the staple of modern polymer industry, their durability under various environmental conditions and degradability after their service life are also essential fields of research. This leads to focus on preparation & characterization of polymer nanocomposite. This article is intended to review the status of worldwide research in this aspect. The successful application of nano particles depends upon both the correct preparation techniques followed by testing through characterization. Surface modification can improve the inherent characteristics of the nano particles and serve to prepare nano composites inexistent in nature. Therefore, some tools as their various properties like electrical, optical and morphological can be used to optimize the preparation of polymer nano composites. This chapter will make an overview about different routes to prepare polymer-based nano composites by extrusion, synthesis of nano particles by sol-gel reactions, sputtering and mainly by physical evaporation deposition method.
Dan Tshiswaka Dan
Soft Nanoscience Letters, Volume 10, pp 17-26; doi:10.4236/snl.2020.102002

Abstract:
Nanotechnologies, nanoparticles and nanomaterials, which are part of everyday life today, are the subject of intense research activities and a certain amount of media coverage. In this article, the concepts of nanotechnologies, nanoparticles and nanosciences are defined and the interest in this scale of the matter is explained by specifying in particular the particular properties of nanoobjects. Large-scale applications of nanoparticles, particularly in the field of chemicals, everyday life and catalysis are presented.
Kentaro Takada, Ken-Ichi Saitoh, Tomohiro Sato, Masanori Takuma, Yoshimasa Takahashi
Soft Nanoscience Letters, Volume 9, pp 45-57; doi:10.4236/snl.2019.94004

Abstract:
Cellulose nanofiber (CNF) is a fibrous and nano-sized substance produced by decomposition of bulk-type cellulose which is a main component of plants. It has high strength comparable to steel, and it shows low environmental load during a cycle of production and disposal. Besides it has many excellent properties and functions such as high rigidity, light-weight, flexibility and shape memory effect, so it is expected as a next-generation new material. Usually it is composed of many cellulose micro fibrils (CMFs) in which molecular chains of cellulose are aggregated in a crystal structure, the knowledge of mechanical properties for each CMF unit is important. Since actual fibrils are complicatedly intertwined, it is also crucial to elucidate the transmission mechanism of force and deformation not only in one fibril but also in between fibrils. How the dynamic and hierarchical structure composed of CMFs responds to bending or torsion is an interesting issue. However, little is known on torsional characteristics (shear modulus, torsional rigidity, etc.) concerning CMF. In general, in a wire-like structure, it is difficult to enhance torsional rigidity and strength, compared with tensile ones. Therefore, in this study, we try to build a hierarchical model of CNF by multiplying CMF fibers and to conduct molecular dynamics simulation for torsional deformation, by using hybrid model between all-atom and united-atoms model. First, shear modulus was estimated for one CMF fibril and it showed a value close to the experimental values. Also, we assume a state in which two CMFs are ideally arranged in parallel, and create a hierarchical structure. We evaluate the dependence on the temperature for the bond strength and toughness in the hierarchical structures. Furthermore, we mentioned the transmission mechanism between components of a hierarchical structure.
Killivalavan Govindarasu, Kavitha Gnanasekaran, Sathyaseelan Balaraman, Baskaran Iruson, Senthilnathan Krishnamoorthy, Babu Padmaraj, Elayaperumal Manikandan, Sivakumar Dhananjayan
Soft Nanoscience Letters, Volume 9, pp 1-16; doi:10.4236/snl.2019.91001

Abstract:
Pure and Cadmium (Cd) doped Cerium oxide nanoparticles (CeNPs) have been synthesised by the simple chemical co-precipitation technique. Cadmium ions of concentrations 1, 3 and 5 mol% were doped to investigate their influence on the structural and optical properties of CeO2. The synthesised samples have been subjected to X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis and high-resolution transmission electron microscopy (HRTEM). The XRD and Raman patterns have witnessed the cubic structure of the cerium oxide nanoparticles. The average particle size of CeO2 was found to be around 10 nm. SEM image has also ascertained that the grain size of pure CeO2 appeared is bigger than that of the Cd-doped, which intern indicates the grain growth upon doping. Besides, the antibacterial activity of the cadmium doped cerium oxide nanoparticles against some human pathogens revealed that they have exhibited the maximum zone of inhibition against gram-positive bacteria than the gram-negative species. Further, the cytotoxic effect of Cd-doped CeO2 sample is examined in cultured (MCF-7, A549 and Hep-2) cell.
Marwa Nabil
Soft Nanoscience Letters, Volume 9, pp 35-44; doi:10.4236/snl.2019.93003

Abstract:
This paper reports the feasibility of synthesis and characterization of nano-porous silicon (NPS) powder and (Nickel/nano-porous silicon, Ni/NPS) nano-composite prepared using dual techniques (alkaline chemical etching process and ultra-sonication technique). The structural and the optical properties of the fabricated structures are inspected using X-ray Diffraction, Fourier Transform Infrared Spectrophotometer, Raman Spec-troscopy, and Fluorescence Spectrophotometer Photoluminescence. All the results have agreed that NPS is one of the most suitable materials used as active material in the LED fabrication; by changing the main factors in the preparation process, so the different physical and chemical properties are obtained. NPS produces two emission regions that correspond to orange-red and dark red; on the other hand, (Ni/NPS) produce the yellow emission. So, the photoluminescence emission is controllable by adjusting the preparation conditions. The optical data recorded here are useful for the production of the nanoscale optical devices.
O. A. Dubovskiy, V. M. Agranovich
Soft Nanoscience Letters, Volume 9, pp 17-33; doi:10.4236/snl.2019.92002

Abstract:
We consider a hybrid heterostructure containing an inorganic quantum well in close proximity with organic material as overlayer. The resonant optical pumping of Frenkel exciton can lead to an efficient indirect pumping of Wannier excitons. As organic material in such a hybrid structure, we consider crystalline tetracene. In tetracene, the singlet exciton energy is close to twice the one of triplet exciton state and singlet exciton fission into two triplets can be efficient. This process in tetracene is thermally activated and we investigate here how the temperature-dependent exciton energy transfer affects the functional properties of hybrid organic-inorganic nanostructures. We have obtained the exact analytical solution of diffusion equation for organics at different temperatures defining different diffusion lengths of excitons. The effectiveness of energy transfer in hybrid with tetracene was calculated by definite method for two selected temperatures that open possibility to operate in full region of temperatures. Temperature dependence of energy transfer opens a new possibility to turn on and off the indirect pumping due to energy transfer from the organic subsystem to the inorganic subsystem.
Tenderwealth Clement Jackson, Timma Oto-Obong Uwah, Akeem Ayodeji Agboke, Blessing Edidiong Udo, Edidiong Michael Udofa
Soft Nanoscience Letters, Volume 08, pp 1-7; doi:10.4236/snl.2018.81001

Abstract:
Silver nanoparticles were synthesized using eco-friendly method with extract of Carica papaya as reducing and stabilizing agent. The silver precursor used was silver nitrate solution. A visible colour change from colourless to reddish brown confirmed the formation of the nanoparticles and the UV-Vis spectroscopy showed surface plasmon resonance of 435 nm for the silver nanoparticle. The mean particle size was 250 nm while the polydispersity index was 0.22. The antimicrobial activity of the synthesized nanoparticles was studied against Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis and Staphylococcus aureus. The silver nanoparticles biosynthesized showed satisfactory antimicrobial activity against the test isolates. Antimicrobial property of the nanoparticles was similar (P > 0.05). Generally, MIC values of the samples against the microorganisms tested ranged from 25 - 100 mg/ml. Pseudomonas aeruginosa was most sensitive while Staphylococcus aureus and Bacillus subtilis were least sensitive to the silver nanoparticles.
Sandhya Yadav, Parmendra Kumar Bajpai
Soft Nanoscience Letters, Volume 8, pp 9-19; doi:10.4236/snl.2018.82002

Abstract:
Transition metal chalcogenide nanocomposite thin films deposited by chemical routes are currently attracting wide attention being inexpensive, simple and have utility for large area applications. The role of substrate becomes very important in film deposition as well as in controlling their properties due to strain induced properties modification and lattice mismatch. CuS/PVA nanocomposite thin films were successfully deposited on glass and silicon substrates using sol-gel technique. Thin films were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), UV-visible (UV-VIS) and Raman spectroscopy. Structural data confirm the amorphous nature of as grown films which transform into crystalline films after annealing at 200°C. The degree of crystallinity seems to be better in film deposited on silicon substrate in comparison to those grown over glass substrate with average crystallite sizes ≅ 4.00 nm and 7.00 nm for films deposited on glass and silicon substrate respectively. Atomic force microscopy (AFM) images in dynamic as well as contact modes display nanoparticles embedded in polymer network. The films surface roughness parameters quantitatively estimated from AFM micrographs are compared. Raman spectra show a sharp peak at ≅474 cm¯1 assigned to S-S stretching mode of S2 ions in films grown on both substrates and associated as due to presence of hexagonal (covellite) crystal structure. Optical band gaps of thin film on glass and silicon substrate are 2.10 eV and 2.02 eV respectively. The effect of substrate on the measured properties is discussed.
Weiwei Pan, Xinlei Zhang, Qin-Fang Liu, Jianbo Wang
Soft Nanoscience Letters, Volume 7, pp 17-26; doi:10.4236/snl.2017.72002

Abstract:
A series of Ni1-xCuxFe2O4 (0.0 ≤ x ≤ 1.0) nanofibers have been synthesized employing electrospinning method at 650°C. The effect of Cu substitution on structural, morphology and magnetic properties of NiFe2O4 nanofibers is reported. The XRD analysis showed the formation of single-phase cubic spinel Ni-Cu ferrite and an increasing behavior of lattice constant. The surface morphology is characterized by SEM, it is investigated that nanofibers have uniform and continuous morphology. The VSM results showed Cu substitution played an important role in magnetic properties of Ni1-xCuxFe2O4. The saturation magnetization (Ms) decreases linearly with increasing Cu2+ content, while coercivity (Hc) has slowly decreased before x ≤ 0.5, and then sharply increased to 723.9 Oe for x = 1.0. The magnetic properties of Ni1-xCuxFe2O4 can be explained in Neel’s model, cation distribution and shape anisotropy.
O. A. Dubovskiy, V. M. Agranovich
Soft Nanoscience Letters, Volume 7, pp 1-15; doi:10.4236/snl.2017.71001

Abstract:
With aim to increase set of modern commercial optoelectronic devices we investigate the optical properties of new triple semiconductor-organics-semiconductor nanostructure having two semiconductor layers with organic layer between. This will be development to majority of modern publications with investigations of only double hybrid nanostructures with one contacting semiconductor layer and one organic layer. It is supposed that the energy of exciton in the first layer is larger than the energy of exciton in organic layer and that the energy of exciton in organic layer is larger in comparison with energy of exciton in second semiconductor layer. It was shown that installation of organics leads to some frequencies at different parameters or to reflection increasing and transmission decrease or to reverted dependence. New recurrent method of inverted calculation for fields is proposed and using this method the frequency dependences of optical characteristics have been calculated. The role of second semiconductor layer in considered triple structure has been estimated.
Huanchun Wang, Lina Qiao, Haomin Xu, Yuanhua Lin, Yang Shen, Cewen Nan
Soft Nanoscience Letters, Volume 6, pp 11-30; doi:10.4236/snl.2016.62002

Abstract:
Energy band engineering and the nature of surface/interface of a semiconductor play a significant role in searching high efficiency photocatalysts. Actually, the active facets, morphology controlling, especially the exposed facets modulation of photocatalysts during preparation are very desirable. In order to achieve high photocatalytic performance, intrinsic mechanism of such anisotropic properties should be fully considered. In this review, we mainly emphasis on the latest research developments of several extensively investigated photocatalysts and their anisotropic photocatalytic properties, as well as the correlation between effective masses anisotropy and photocatalytic properties. It will be helpful to understand the photocatalytic mechanism and promote rational development of photocatalyst for wide applications.
Dong Hun Shin, Yun Seok Choi, Dong Jin Ku, Yong Cheol Hong,
Soft Nanoscience Letters, Volume 6, pp 31-36; doi:10.4236/snl.2016.62003

Abstract:
The silicon oxide nano-powders (SiOx-NPs) were obtained in an atmospheric microwave plasma torch using a gas-phase silicon tetrachloride (SiCl4) with N2 and H2. The gas-phase SiCl4 was injected with H2 gas into the microwave plasma torch generated by N2 and air swirl gas, and then the dark brown powders were deposited on the inner wall of a quartz tube. The sample was analyzed by an X-ray photoelectron spectroscopy (XPS), a scanning electron microscope (SEM), an energy dispersive spectrometer (EDS), and an X-ray diffraction (XRD). The average size and oxidation x values of synthesized SiOx-NPs were approximately 230 nm and 0.91, respectively. Furthermore, the volumetric charge capacity is 1127 mAh/g and has 89.2% retention after 100 cycles.
, Yogesh Choudhari, Mangeshkumar Padame
Soft Nanoscience Letters, Volume 6, pp 1-10; doi:10.4236/snl.2016.61001

Abstract:
The aim of present study was to use QbD approaches to evaluate the effect of independent product variables and their interaction on particle size of sodium fluoride and then obtain the optimized experimental condition for predefined particle size of sodium fluoride. The sodium fluoride is mainly used in dental preparation for delivering the fluoride ion to the tooth enamel for that nano-particle size is required. Nowadays the milling process is used to reduce the particle size. But that process has some limitations due to crystalline nature of sodium fluoride; for overcoming those limitations, lyophilization method is used. A 43 level full factorial design was used to study the significant influence of process and product variables i.e. 1) Concentration of sodium fluoride, 2) Concentration of PVP, 3) Sample volume, 4) Drying surface, on particle size of sodium fluoride. The experimental design result shows that independent product variables significantly modify the structure and improve particle size reduction of sodium fluoride.
Naraavula Suresh Kumar, Katrapally Vijaya Kumar
Soft Nanoscience Letters, Volume 6, pp 37-44; doi:10.4236/snl.2016.63004

Abstract:
Bismuth substituted cobalt nano ferrites with the chemical composition Co Bix Fe2-x O4 (x = 0.00, 0.05, 0.10, 0.15, 0.20 & 0.25) were prepared by sol-gel combustion method. The phase identification of prepared samples is characterised by X-ray powder diffraction (XRD) method, which confirms the formation of a single phase fcc spinal structure. The mean crystallite sizes of all prepared samples were obtained within the range of 21 (±5) nm. Transmission Electron Microscopy (TEM) images also confirmed the crystallite size of all the synthesised samples was in nano range. With the effect of Bi3+ ion substitution on spinal cobalt ferrite, the magnetic properties were investigated by using Vibration Sample Magnetometer (VSM). The obtained hysteresis (M-H) curves of all the samples were analysed under the applied magnetic field of range ± 10 K Oe at 300 K. The magnetic properties such as saturation magnetisation (Ms), remnant magnetization (Mr) and coercivity (Hc) values are tabulated, which show a decrease in trend as the bismuth ion concentration increases. This is due to the addition of Bi3+ ion in the place of Fe3+ ion (octahedral site) and hence the Bi3+-Fe3+ ion interaction predominates as compared with the Fe2+-Fe3+ ion interaction. The data obtained from magnetic studies, the variation among the magnetic properties have been investigated for all the prepared samples.
, Takashi Arai, Takashi Tomita, , Akihiro Yoshino, Keijiro Taga, , Motoyuki Itoh, Yoshitaka Taguchi
Soft Nanoscience Letters, Volume 6, pp 45-55; doi:10.4236/snl.2016.64005

Abstract:
Compounds for a series of alkyltrimethylammonium salicylates (C12TA-Sal through C16TA-Sal) were synthesized. Their physical properties in aqueous solutions were investigated by conductometry, viscometry, vortex inhibition, viscoelastic recoil and swirling decay time from a view point of drag reduction. For critical micelle concentrations (CMC) obtained for a series of compounds by conductometry, it was found that a linear relation of the form, log(CMC)= 4.088 − 0.305*Nc (Nc: carbon number in the alkyl chain), holds. From the viscosity measurement, all the compounds showed viscosity increase above their CMC. Vortex inhibition was observed above the CMC for the compounds with the chain length longer than C13. Viscoelastic recoil was observed above the concentration of one and a half times the CMC for the compounds with alkyl chain length longer than C14.
, Carmen Morant
Soft Nanoscience Letters, Volume 5, pp 1-2; doi:10.4236/snl.2015.51001

Abstract:
Recently, a large part of the advances in nanotechnology have been directed towards the development of high-speed electronics, more efficient catalysts, and sensors. This latter group of applications has great relevance and unprecedented development potential for the coming years.So far, some of the main objectives for the development of sensors have focused on making more sensitive, effective and specific sensing devices.The improvement of these systems and the increase of specificity are clearly associated with a decrease in size of the components, which can lead to obtaining more rapid action, almost in real time. Nanomaterials currently used in sensor development include a long list of nanostructured systems, as for example: metal nanotubes, nanowires, nanofibers, nanocomposites, nanorods, nanoparticles, nanostructured polymers, and different allotropes of carbon as carbon nanotubes, graphene or fullerenes, among others.
, , Tanu Mimani Rattan, Venkataramaniah Kamisetti
Soft Nanoscience Letters, Volume 5, pp 13-20; doi:10.4236/snl.2015.52003

Abstract:
Aceclofenac is a new generational Non-Steroidal Anti-Inflammatory Drug (NSAID), and is considered a better alternative to the popular pain-killer diclofenac, as it overcomes some of the adverse gastrointestinal and cardiac side effects associated with the latter. However, the bioavailability of the drug remains limited due to low aqueous solubility (0.058 μg/mL) and poor dissolution characteristics. Hence, improving its dissolution characteristics is of prime significance in order to establish its optimal therapeutic efficacy. In an effort to tackle this issue, we report the use of novel Soluplus®-based nanocomposites, prepared from emulsion templates, as effective drug loading agent for aceclofenac. Nanoemulsion templates were prepared by high-shear homogenization using a probe sonicator. The emulsions were subsequently lyophilized to obtain free flowing powders. The amorphization of the drug with increasing polymer content was clearly observed from powder X-ray diffractogram, while the drug-polymer interaction was explored by FTIR spectroscopy. The phase purity and homogeneity of the formulation was characterized using Differential Scanning Calorimetry. The dissolution profiles of the formulations were established by an USP paddle apparatus. Phase solubility study was conducted to evaluate the effect of polymer concentration on aqueous solubility of aceclofenac. The values of Gibbs-free energy (ΔG°tr) associated with the aqueous solubility of aceclofenac in the presence of Soluplus was used to optimize the polymer content. The in vitro dissolution rates of aceclofenac from the nanoparticles were significantly higher compared to the pure drug. Thus, Soluplus nanoparticles provide promising formulations for the improvement of the dissolution profiles and thus, the bioavailability, of aceclofenac.
Ezzeldeen S. El-Denshary, Abdulhadi Aljawish, Aziza A. El-Nekeety, Nabila S. Hassan, Raghda H. Saleh, Bertrand H. Rihn,
Soft Nanoscience Letters, Volume 5, pp 36-51; doi:10.4236/snl.2015.52005

Abstract:
This study was conducted to prepare chitosan nanoparticles (CNPs), to determine their properties and to evaluate the synergistic protective role of CNPs alone or in combination with quercetin (Q) against oxidative stress and hepatotoxicity in rats. Female Sprague-Dawley rats were divided into 12 groups (7 rats/group) and were maintained on their respective diet for 3 weeks as follow: control group, the group treated with CCl4 (100 mg/kg b.w twice a week); the groups received CNPs at low and high doses (140 and 280 mg/kg b.w); the group received Q (50 mg/kg b.w); the groups received CNPs at the low or high doses plus Q and the groups treated with CCl4 plus Q and/or CNPs at the two tested doses. Blood and liver samples were collected at the end of experiment period for biochemical and histological studies. The results indicated that chitosan showed deacetylation degree of 17.5% and 19.2% and the molar mass average of monomer was 168.35 g/mol and 169.1 g/mol by UV and IR methods respectively. The particle size of CNPs was around 100 nm with a rough surface. The in vivo results revealed that CCl4 induced biochemical and histological changes typical to those reported in the literature. Animals treated with CNPs at the two tested doses alone or in combination with Q were comparable to the control. CNPs alone or plus Q succeeded to induce significant improvements in the biochemical parameters and histological picture of the liver in rats treated with CCl4. This improvement was in dose-dependent manner for CNPs and was more pronounced in the group treated with the high dose plus Q. It could be concluded that both CNPs and Q could induce protection against hepatotoxicity. Consequently, CNPs was a promise candidate as drug delivery in liver diseases treatments.
Pratima Parashar Pandey
Soft Nanoscience Letters, Volume 5, pp 3-11; doi:10.4236/snl.2015.51002

Abstract:
Silver particulate thin films on softened polymer blends of Polystyrene (PS)/Poly(2-vinyl pyridine) (P2VP), PS/Poly(4-vinylpyridine) (P4VP), and Poly(vinylpyrollidone) (PVP)/P4VP at a rate of 0.4 nm/s held at a temperature of 457 K in vacuum of 8 × 10-6 Torr by evaporation are deposited. These silver films were characterized by their electrical behavior, optical properties and Scanning electron microscopy (SEM). Silver films deposited on softened PS, and PVP give rise to a very high room temperature resistance approaching that of the substrate resistance due to the formation of a highly agglomerated structure. On the other hand, silver films on softened P2VP and P4VP give rise to a room temperature resistance in the range of tens to a few hundred MΩ/ which is desirable for device applications. Silver films on the composites of PS/P2VP, PS/P4VP and PVP/P4VP show resistances at room temperature. The optical and plasmonic response of Ag nanoparticles onto thin layers of blends shows encapsulation of nanoparticles. The electrical properties and SEM of silver nanoparticles on the thin layers of polymer blends indicate the formation of much smaller, narrower dispersion and wide size distribution.
, Jiban Podder
Soft Nanoscience Letters, Volume 5, pp 55-64; doi:10.4236/snl.2015.54007

Abstract:
The chemical bath deposition (CBD) technique was used for the synthesis of the tin oxide (SnO2) thin films. X-ray diffraction (XRD) was employed to find the crystallite size by using Debye Scherrer’s formula. The surface morphology of SnO2 films was analyzed by the scanning electron microscopic (SEM) studies. The FT-IR spectrum exhibits the strong presence of SnO2. The optical properties of the SnO2 thin films were determined using UV-Visible spectrum. The dielectric studies were carried out at different frequencies and at different temperatures for the prepared SnO2 thin films. Further, electronic properties, such as valence electron plasma energy, average energy gap or Penn gap, Fermi energy and electronic polarizability of the SnO2 thin films, were determined. The ac conductivity of the SnO2 thin films increases with increase in temperature and frequency. The activation energy was determined by using dc electrical conductivity measurement. The Hall properties were also calculated.
Chhatrapati Parida, Sarat Kumar Dash, Pinaki Chaterjee
Soft Nanoscience Letters, Volume 5, pp 65-72; doi:10.4236/snl.2015.54008

Abstract:
The influence of cellulose nano fibers extracted from the fruit of luffa cylindrica (LC) on the tensile, flexural and impact properties of composite materials using poly lactic acid (PLA) processed by micro compounding and injection molding was studied. Preliminary results suggested promising mechanical properties. The impact strength, tensile strength and flexural strength of the composites increased with incorporation of very low content of LC fiber up to 2 wt%. But when the wt of LC fiber in the composite increased (5 wt% and 10 wt%), mechanical strength of the composites reduced probably due to agglomeration of cellulose fibers. However, modulus of composites was enhanced with increase in wt of fiber content in the composites. Before reinforcement, the LC fibers were modified with calcium phosphate in order to explore the possibilities of using these composites in biomedical industries. The novelty of this work is that there is no use of compatiblizer and coupling agent during the processing so that the cost of processing is reduced.
Mosaad A. Abdel-Wahhab, Ezzeldein S. El-Denshary, Aziza A. El-Nekeety, Khaled G. Abdel-Wahhab, , Mohamed F. ElYamany, , Fathia A. Mannaa, Mohamed N. Q. Shaiea, Reda A. Gado, et al.
Soft Nanoscience Letters, Volume 5, pp 21-35; doi:10.4236/snl.2015.52004

Abstract:
The aim of the current study was to prepare organo-modified nano montmorillonite (OMNM) and to evaluate its chemopreventive effects against the hapatonephrotoxicity induced by aflatoxin B1 (AFB1) and ochratoxin A (OA) singly or in combination in rats. OMNM was prepared using Cetyltrimethylammoniumbromide (CTAB) as organic modifier. Eighty male Sprague Dawley were divided into 8 groups and treated for 8 weeks as follow: the control group; the group treated orally with AFB1 (80 μg/kg b.w.); the group treated with OA (100 μg/kg b.w.); the group treated with AFB1 plus OA, the group treated with OMNM (5 g/kg diet) and the groups treated with AFB1 and/or OA plus OMNM. At the end of treatment period, blood and tissue samples were collected from all animals for biochemical and histological analysis. The results revealed that the expansion in the basal spacing of the montmorillonite due to the intercalation of CTAB was 7.20 Å and the average particle size of OMNM was 120 nm. The in vivo results indicated that treatment with both AFB1 and OA singly or in combination resulted in a significant increase in liver and kidney function parameters, oxidative stress and tumor markers accompanied with a significant decrease in antioxidant enzyme activities and significant histological changes in liver and kidney tissues. These changes were severe in the group received the combined treatment of AFB1 and OA. OMNM alone did not show any toxic effect and it succeeded to prevent or at least diminish the toxic effects and the histological changes in liver and kidney. It can be concluded that treatment with AFB1 and OA has a synergistic toxic effects and OMNM is safe and it is a promise candidate as an additive to protect against the exposure to multi-mycotoxins in high risk population.
Mosaad A. Abdel-Wahhab, Francisco Márquez
Soft Nanoscience Letters, Volume 5, pp 53-54; doi:10.4236/snl.2015.53006

Abstract:
Nowadays, nanomaterials have become an emerging field that has shown great promise in the development of novel diagnostic, imaging and therapeutic agents for a variety of diseases, including cancer, due to their nanoscale size effects and increased surface area. In comparison to their larger counterparts, nanomaterials have unique physicochemical and biological properties including size, shape, chemical composition, surface structure and charge, aggregation and agglomeration, and solubility which can affect their interactions with biomolecules and cells. Nanoparticles (NPs) with size-tunable light emission have demonstrated an impressive potential as high-efficiency delivery transporters for biomolecules into cells, being used to produce exceptional images of tumor sites. Moreover, NPs delivery system has been widely applied in pharmaceutical field to enhance absorption of bioactive compounds since they can interact with several phytochemicals by hydrogen bonds and hydrophobic interactions to encapsulate these phytochemicals in NPs and thus enhance aqueous solubility of the chemicals. Moreover, NPs also can prevent against oxidation/degradation of the phytochemicals encapsulated in the gastrointestinal tract and can be taken directly up by epithelial cells in the small intestine resulting in the increase of absorption and bioavailability of phytochemicals. In general, there are two specific fields of utilization of intrinsically active NPs as pharmacologic agents including oxidative-related pathologies and cancer. On the other hand, Redox active NPs have been shown to ameliorate many clinically relevant pathological disorders that implicate oxidative stress, reducing the oxidative burden and alleviating many important symptoms. Such NPs act either in a catalytic way resembling the action of antioxidant enzymes such as catalase and superoxide dismutase, or as activating surfaces to facilitate reactions between the aqueous environment and the reactive oxygen species present at high level in the pathological tissues.
, , Soheila Mardani
Soft Nanoscience Letters, Volume 4, pp 1-5; doi:10.4236/snl.2014.41001

Abstract:
ZnO films have been deposited on glass slide substrates at room temperature by thermal evaporation technique. The prepared samples were annealed at temperature of 300°C and 400°C in air atmosphere. Optical and structural properties of as-deposited films have been compared by that of the annealed samples. X-ray diffraction (XRD) patterns of the obtained films showed that they have polycrystalline and exhibit wurtzite structure. Micro-structural properties such as mean crystallite size and micro-strain were discussed from XRD peak broadening. Optical properties were identified by measuring transmittance using UV-Vis spectrophotometer. The optical constants such as the refractive index n, extinction coefficient k as well as films’ thickness were calculated in the spectral range of 350-800 nm from transmittance data using a reverse engineering method (point-wise unconstrained minimization approach, PUMA). Dispersion of refractive index shows similar trend as Cauchy relation. Absorption coefficient depicts a maximal value around 3.33 eV for annealed samples. Using balance between electrical power and emissive power, the temperature of tungsten furnace was calculated under deposition condition. The connection between temperature and vapor pressure of ZnO was estimated by the Clausius-Clapyeron equation and thermochemical data.
Guocai Xu, Shengtao Gao, Xiaoli Ji, Xiaomei Zhang
Soft Nanoscience Letters, Volume 4, pp 15-23; doi:10.4236/snl.2014.42003

Abstract:
Nanosilver/Poly(2-acrylamido-2-methylpropanesulfonate sodium (AMPS)) composites were synthesized with sliver nitrate solution containing AMPS monomer in situ by microwave radiation without addition of any reducer. The composites were characterized by means of UV-Vis, XRD, FTIR, TEM and XPS respectively. The results show that silver nanoparticles are dispersed highly and homogeneously in PAMPS matrix and possessed face-centered cubic structure. The morphology of nanosilver particles is not affected by microwave treatment and AMPS polymerization. XPS analysis reveals that there is an interaction among silver nanoparticles with nitrogen atoms and carbonyl oxygen atoms from AMPS polymer. Thermoanalysis proves that thermal stability of the PAMPS nanocomposites is decreasing with silver nanoparticles dispersed in the composites. The mechanism of silver ion reduced to nanosilver particles catalysized by PAMPS under microwave is discussed.
, Carmen Morant
Soft Nanoscience Letters, Volume 4, pp 51-52; doi:10.4236/snl.2014.43007

Abstract:
As expected for years, nanotechnology has revolutionized engineering, biology, chemistry, physics and medicine of today. These disciplines are evolving thanks to the ongoing development of new materials and applications. Nanomedicine, as application of nanotechnology in the field of health care, has undergone unprecedented development. Some of these changes have real applications as, for example, the use of nanoparticles in MRI imaging, in hyperthermia, in immunotherapy, or to improve the bioavailability of drugs, among others [1]-[3]. When a drug is administered to a patient, the blood distributes it throughout the body. In the case of very localized diseases (i.e. tumors), only a small fraction of the drug reaches the target. Chemotherapy is one of the most aggressive treatment options used in some types of cancer, and is usually administered intravenously. In this type of therapy, the drug circulates throughout the body, reaching and destroying healthy and cancerous tissues, producing side effects throughout the body, sometimes with serious consequences for the health of the patient (nephrotoxicity, cardiotoxicity, peripheral neuropathy, anemia, etc.). Among the many applications of nanotechnology, the fabrication of nanostructures capable of safely transporting these drugs is seen as a strategy for reducing these side effects. Nanoparticles are able to carry and release the drug in the right place and with the required dose, greatly reducing the problems associated with direct treatment with these drugs. In recent years, there have been continuous improvements in the design and development of new tailor-made drug delivery systems [4], including hollow magnetic nanoparticles, liposomal structures, dendrimers, nanoporous silicon, etc. These structures can be obtained with different molecular weights (in the case of polymers), structures, shapes, and even with the appropriate functional groups for interaction at the desired positions. However, a great effort is still required to solve many of the current problems [5], including toxicity, aggregation, solubility and stability in the human body, physiological processes of elimination, identification of targets by highly specific receptors, controlled drug release over time, etc.
, Saúl Robles Manuel, Facundo Ruiz
Soft Nanoscience Letters, Volume 4, pp 53-62; doi:10.4236/snl.2014.43008

Abstract:
In this work, titanium dioxide (TiO2) nanoparticles were functionalized with maleic anhydride (MA), using a non-polar (toluene) and polar protic (ethanol) solvents. The concentrations of MA in the reaction were varied to obtain the desired degree of functionalization. The samples were characterized with Fourier Transform Infrared Spectroscopy (FTIR), Diffuse Reflectance UV-Vis Spectroscopy (DRS), Thermal Analysis (TGA-DTA) and Nitrogen Adsorption (BET). The physical adsorption of organic molecules was eliminated by washing a number of times in water. Chemical stability between solid-organic phases was confirmed by TOC and thermal analysis. FT-IR and DRS results clearly show the chemical adsorption of MA on the TiO2. The UV-Vis spectroscopy is claimed to be a suitable technique to determine the achievement of TiO2 functionalization. Two different adsorptions geometries of MA were proposed. The presence of MA on the surface TiO2 increases the band gap. These results imply that TiO2 can be excited with less energy and increase the absorption of light in the visible region. The effectiveness of the functionalized nanoparticles to interact with organic materials is currently being studied with the intention of applying them in the energy and environmental sanitation fields.
, , M. Z. MatJafri
Soft Nanoscience Letters, Volume 4, pp 83-89; doi:10.4236/snl.2014.44012

Abstract:
In this work ITO thin film annealing was carried out using a CW CO2 laser beam for ITO thin film annealing over a 1 cm2 area with a temperature higher than 250°C to obtain ITO grains with excellent structural quality thin films. The obtained ITO films were characterized for crystallization, surface morphology, electrical and optical properties, which has theoretical significance and application value. ITO thin films are deposited on glass substrates by sputter coater system (RF) from a high density target (In2O3-SnO2, 90-10 wt%). After deposition, ITO thin films have been irradiated by CW CO2 laser (λ = 10.6 μm) with power ranging from 1 to 10 watt. These films were annealed at temperatures 250°C, 350°C, and 450°C in the air for 20 minutes using different laser power. The main incentive was to develop a low temperature process for ITO thin films, which typically required a 350°C anneal to crystallize and achieve optimum optical and electrical properties. The XRD results showed that 350°C temperature laser annealing could crystallize ITO with a strong (222) preferred orientation and its grain size increased from 29.27 nm to 48.63 nm. The structure, optical transmission, energy gap, resistivity and sheet resistance of the ITO thin films were systematically investigated as a function of laser post annealing temperature. It was found that the lowest resistivity was 2.9 × 10-4 Ω-cm and that sheet resistance was 14.5 Ω/sq. And the highest optical transmittance (98.65%) of ITO films was obtained at 350°C annealing temperature.
Thai-Hoa Tran, Sy-Thang Ho,
Soft Nanoscience Letters, Volume 4, pp 6-14; doi:10.4236/snl.2014.41002

Abstract:
Hierarchical phases of the biomaterials can be used as template to transfer their intricate organization into biomimic inorganic solids. Herein, hierarchical mesoporous silica films with aligned pores have been templated by nanofibrillar alginic acid. An aqueous suspension of the alginic acid nanofibers was prepared by treating the brown seaweeds with sodium carbonate solution and subsequent precipitation in dilute hydrochloric acid. The alginic acid nanofibers of the organize into a hierarchical aligned phase in an acetic acid-sodium acetate buffer that was used to template silica-alginic acid composite films by evaporation induced self-assembly of alkoxysilane with nanofibrillar alginic acid. Calcination of the alginic acid template afforded hierarchical mesoporous silica glasses. Carbonization of the silica-alginic acid composites and subsequent etching the silica recovered mesoporous carbon supercapacitors.
Kirsten Parratt, Johnathan M. Yao, Gerald R. Poirier,
Soft Nanoscience Letters, Volume 4, pp 63-68; doi:10.4236/snl.2014.43009

Abstract:
Nacre’s brick and mortar structure has been motivating innovations in biomimetic materials for decades. However, there is still room to improve understanding of the structure of the organic layer in order to engineer better biomimetic composites. A plasma-etching technique that allows for the selective removal of some organic components from individual layers is developed. We conclude that this technique enables a closer examination of the organic layer such that the locations and mechanical properties of individual components can be determined. A methodology for examining nacre samples that have not been demineralized provides a more accurate substrate for understanding the structure-property relationships of the organic layer in native nacre.
, Jayakrishna Khatei
Soft Nanoscience Letters, Volume 4, pp 69-74; doi:10.4236/snl.2014.43010

Abstract:
A simple one-pot hydrothermal method to grow luminescent CdTe nanorods on porous anodized aluminum oxide (AAO) template is described. These CdTe nanorods on the AAO template were further applied as an optical probe to detect divalent heavy metal ions such as Hg, Pb, Mg and Zn, by examining its photoluminescence (PL) responses. The presence of Pb and Hg ions quenched the photoluminescence (PL) of the CdTe nanorods where as Zn and Mg ions enhanced it with the effect of red shift in the peak position respectively. These PL enhancements/quenching of the nanorods after exposing to the divalent ions were explained on the basis of the active surface related recombination, which depends on the direction of carrier transfer mechanism i.e. from nanorods to the surface adsorbed metal ions or vice-versa and is attributed to the alignment of bands thus formed. The luminescent CdTe nanorods grown on AAO template was found to be effective in sensing metal ions (Pb, Hg, Zn and Mg) up to a micro-molar concentration.
Soft Nanoscience Letters, Volume 4, pp 75-81; doi:10.4236/snl.2014.43011

Abstract:
In this paper functionalized multiwall carbon nanotubes (FMWCNT) were modified using atenolol as a class of drugs that were used in cardiovascular diseases containing reactable nitrogen, which could attach chemically to functionalized MWCNT. This product was characterized by Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy. These spectrums proved the existence of nitrogen atoms of amide due to new functional group. The morphology were also determined by scanning electron microscopy (SEM) and showed that this product was synthesized in the nanometer dimension. Thermal gravimetery (TGA) analysis was also used to evaluate thermal properties.
Sergey A. Kovalevskiy, Fedor I. Dalidchik, Galina V. Nizova, Evgenii M. Balashov
Soft Nanoscience Letters, Volume 4, pp 24-30; doi:10.4236/snl.2014.42004

Abstract:
Scanning tunneling spectroscopy (STS) was used for investigation of rectification properties of molecules with spatial asymmetry. The molecules of cetyltrimethylammonium derivatives of 10-molibdo-2-vanadophosphate-anions [PMo10V2O40]﹣5 (CTMVA) were adsorbed on a surface of pyrolytic graphite (HOPG). Consequently, both good diode properties and J(V)-curves reproducibility of the film were revealed. The validity of the single-level model for the evaluation of the system parameters is discussed.
Burcu Arman,
Soft Nanoscience Letters, Volume 4, pp 42-49; doi:10.4236/snl.2014.42006

Abstract:
Poly (acrylonitrile-co-vinyl acetate)/polypyrrole composite particles with uniform size and morphology have been synthesized using one-step polymerization that involves swelling and coating of polypyrrole (PPy) into P (AN-co-VAc) latex nanoparticles. As an initial stage, free radical copolymerization of acrylonitrile (AN) and vinyl acetate (VAc) was synthesized by emulsion polymerization using ammonium persulfate (APS) and dodecyl benzene sulfonic acid salt (DBSA) as a surfactant. P (AN-co-VAc)/PPy composites were obtained first time by in situ addition of the pyrrole into the reaction medium. The electrospun P (AN-co-VAc)/PPy nanofibers were obtained from the nanoparticles with better properties and the effect of PPy on the morphology of nanofibers was studied by scanning electron microscopy (SEM). High degree of homogeneity and molecular order induced by molecular dispersion of polypyrrole on copolymer matrix without phase separation improve the transport properties and stability of polypyrrole, which are critical for high-performance organic electronics.
Jorge Hernández Bourdon, Francisco Márquez Linares
Soft Nanoscience Letters, Volume 4, pp 31-41; doi:10.4236/snl.2014.42005

Abstract:
The formation of disinfection by-products (DBPs) during chlorination of drinking water is an issue which has drawn significant scientific attention due to the possible adverse effects that these compounds have on human health and the formation of another DBPs. Factors that affect the formation of DBPs include: chlorine dose and residue, contact time, temperature, pH and natural organic matter (NOM). The most frequently detected DBPs in drinking water are trihalomethanes (THMs) and haloacetic acids (HAAs). The MCLs are standards established by the United States Environmental Protection Agency (USEPA) for drinking water quality established in Stage 1, Disinfectants and Disinfection Byproducts Rule (DBPR), and they limit the amount of potentially hazardous substances that are allowed in drinking water. The water quality data for THMs were evaluated in the Puerto Rico Aqueduct and Sewer Authority (PRASA). During this evaluation, the THMs exceeded the maximum contamination limit (MCLs) for the Comerio Water Treatment Plant (CWTP). USEPA classified the THMs as Group B2 carcinogens (shown to cause cancer in laboratory animals). This research evaluated the THMs concentrations in the following sampling sites: CWTP, Río Hondo and Pinas Abajo schools, Comerio Health Center (CDT), and the Vázquez Ortiz family, in the municipality of Comerio Puerto Rcio. The results show that the factors affecting the formation of THMs occur in different concentrations across the distribution line. There are not specific ranges to determine the formation of THMs in drinking water when the chemical and physical parameters were evaluated. Three different nanostructured materials (graphene, mordenite (MOR) and multiwalled carbon nanotubes (MWCNTs)) were used in this research, to reduce the THMs formation by adsorption in specific contact times. The results showed that graphene is the best nanomaterial to reduce THMs in drinking water. Graphene can reduce 80 parts per billion (ppb) of THMs in about 2 hours. In addition mordenite can reduce approximately 80 ppb of THMs and MWCNTs adsorbs 71 ppb of THMs in the same period of time respectively. In order to complement the adsorption results previously obtained, total organic carbon (TOC) analyses were measured, after different contact times with the nanomaterials. During the first 30 minutes, graphene C/Co was reduced to c.a. 0.9, in presence of each THMs solution. MWCNTs and MOR show similar adsorptions trends in comparison with graphene.
Gomathinayagam Kanthimathi, Petchimuhtu Kotteeswaran, Muregasan Muthuraman, , Muniasamy Kottaisamy
Soft Nanoscience Letters, Volume 3, pp 75-78; doi:10.4236/snl.2013.34013

Abstract:
Adsorption of Cu(II) and Co(II) from aqueous solutions on synthetic nano Fe3O4 has been studied. The effect of experimental parameters such as initial concentration of the metal ions, adsorbent dosage, contact time and pH has been investigated. Optimum removal efficiency of Cu(II) ion was found to be 97.8% with the dose rate of 1.07 g/L in 60 minutes at pH = 5.5 and for Co(II) ion, it was found to be 99.2% with the dose rate of2.57 g/L in 10 minutes at pH = 5.4. The removal of Co(II) ions require only 10 minutes with the efficient removal of 99.2%, whereas Cu(II) ions require 60 minutes with the maximum removal of 97.8%. In order to understand the effective removal of Cu(II) and Co(II) ions on Fe3O4, room temperature magnetic measurement was carried out using Vibrational Spectrum Magnetometer (VSM), before and after adsorption with a maximum applied magnetic field of 20,000 G.
K. J. Gururaj, B. E. Kumara Swamy
Soft Nanoscience Letters, Volume 3, pp 20-22; doi:10.4236/snl.2013.34a006

Abstract:
Titania nano particles were synthesized at carbon paste electrode by cyclic voltammetry and then it was employed for the determination of acetaminophen in phosphate buffer at pH 7.4. Carbon paste electrode with titania nano particle displayed excellent electrochemically catalytic activities by shifting the oxidation potential of acetaminophen towards the negative side. The mass transfer process at electrochemical interface was diffusion controlled. Electrochemical techniques such as, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization methods were used to measure the resistance of the electrodes. The resistance of the titanium electrode decreased in two orders when compared to the bare carbon paste electrode; the decrease in the resistance of the electrode and increase in the surface area of the electrode are responsible for the negative shifting of the oxidation potential of acetaminophen. The present method was applied to the determination of actetaminophen in paracetamol tablet, urine and blood sample by using standard addition method and the obtained results were satisfactory with a good recovery of 98%.
, Venkataraman Jayaraman, Thiagarajan Gnanasekaran
Soft Nanoscience Letters, Volume 3, pp 39-42; doi:10.4236/snl.2013.34a011

Abstract:
A soft-chemical method has been developed for the synthesis of nano-crystalline powders of silver decamolybdate. Gas sensing characteristics of this composition both in porous pellet and thin film configurations were investigated. The compound Ag6Mo10O33 was found to sense selectively ammonia at 503 K. Above 503 K it has significant cross sensitivity to petroleum gas (PG). Spin coated thin films exhibited selective sensing towards PG.
Z. H. Ibupoto, K. Khun, V. Beni,
Soft Nanoscience Letters, Volume 3, pp 46-50; doi:10.4236/snl.2013.34A013

Abstract:
In this study, novel nickel oxide (NiO) flowers like nanostructures were fabricated onto gold coated glass substrate by hydrothermal method using high alkaline pH medium. The structural study of nickel oxide nanostructures was performed by scanning electron microscopy (SEM) and X-ray differaction (XRD) techniques. Nickel oxide nanostructures are highly dense, uniform and possess good crystalline quality. The so prepared structures were investigated for their electrochemical properties by cyclic voltammetry and amperometric techniques. The nickel oxide flower like morphology has shown good electrochemical performances for the oxidation of glucose. The presented sensing material was able to detected glucose in a wide range of concentration of 0.001 mM to 8 mM with a high sensitivity (123 μmA/mM) and regression coefficient of 0.99. Moreover, the NiO nanostructures based sensor is highly reproducible, stable, exhibiting a fast response time and selective in the response. All the obtained results indicate the potential use of this material in the development of enzyme free sensors for the detection of glucose.
Poonam Silotia, Seema Dabas, Aditya Saxena,
Soft Nanoscience Letters, Volume 3, pp 7-10; doi:10.4236/snl.2013.31002

Abstract:
Recently measured thermal conductivity in single-walled carbon nanotube ropes in the temperature range 8 - 350 K has been explained using an anisotropic dynamical model which not only takes into account the quasi two-dimensional nature of the folded graphene sheets that forms the nanotubes, but also the intertube coupling, in addition to the phonon frequency and dimensionality dependent relaxation time of phonon-phonon scattering and interaction.
Elseddik M Abdelkader,
Soft Nanoscience Letters, Volume 3, pp 22-27; doi:10.4236/snl.2013.31005

Abstract:
We report here on the synthesis of nanoparticles (NPs) of sodium halide (NaX; X = F, Cl, Br, I) salts using reverse micelles (water/dioctylsodiumsulfosuccinate/toluene) with the resulting NPs having diameters of 1.5 to 2.5 nm. The initial core of reverse micelle contains a water-soluble salt. After evaporation of the volatile compounds under vacuum (water and toluene), NaX NPs are produced with an AOT surfactant cap. The NaX NPs redisperse in toluene. In contrast to previous syntheses of soluble salt NPs, Na+ ions from the surfactant are found to completely exchange with the salt in the initial core of the reverse micelles. The resulting NPs were analyzed with dynamic light scattering (DLS), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) which confirmed the exchange mechanism. Experimental results are compared and found to be in agreement with the recently published model by Bandopadhyaya and coworkers.
M. Sethupathy, V. Sethuraman, P. Manisankar, M. Sethupathy, V. Sethuraman, P. Manisankar
Soft Nanoscience Letters, Volume 03, pp 37-43; doi:10.4236/snl.2013.32007

Abstract:
Superhydrophobic poly(vinylidene fluoride) PVDF-SiO2 composite membranes with different % of SiO2 contents were prepared by electrospinning. The surface morphologies of the membranes are characterized by using scanning electron microscopy. The nanofibers in the membranes were stacked in layers to produce fully interconnected pores that resulted in high porosity. The incorporation of SiO2 into the nanofiber membrane improved the ionic conductivity from 0.2428 × 10-4Scm-1 to 7.731 × 10-4Scm-1 at room temperature. The surface roughness of the membranes increased with increasing the SiO2 content, while the average diameter of nanofibers was rarely affected. Superhydrophobic PVDF membrane with a contact angle larger than 136° was prepared by the electrospinning of the SiO2 functionalized PVDF. The surface composition of the membranes is analyzed by using FTIR and the contact angles and water drops on the surface of the membrane are measured. The contact angle experimental results of PVDF-SiO2 composite membranes showed an improvement of hydrophobicity with % of nano SiO2.
Soft Nanoscience Letters, Volume 3, pp 83-86; doi:10.4236/snl.2013.34015

Abstract:
Facile method of synthesizing organic-inorganic solid foam in complex structure is presented. The synthesis method is based on the use of neutral surfactant (1-hexadecylamine, C16H33NH2) as structure directing agent and inorganic salt (vanadium nitride, VN) as precursor. The foam containing C16H33NH2 has been synthesized by evolution of oxygen gas produced spontaneously from hydrogen peroxide through a viscous VN gel. The foam from the precursor of 0.5 gVN nanopowder grows gradually, reaching about 0.3 liters 10 minutes after excess addition of H2O2 and stirring. The ultralight, crystalline material made via foam processing was observed by XRD, SEM, TEM, and FTIR.
, Oleksandr V. Bondar, Oleg V. Sobol, Vyacheslav M. Beresnev
Soft Nanoscience Letters, Volume 3, pp 46-51; doi:10.4236/snl.2013.33009

Abstract:
Using such unique methods of analysis as slow positron beam (SPB), RBS, μ-PIXE (proton microbeam), XRD, SEM with EDS, XPS, nanohardness and elastic modulus measurements, we studied superhard nanostructure Ti-Si-N coatings, which were deposited using Cathodic-PVD method, before and after annealing at the temperature of 600°C for 30 minutes. It is shown in the paper that redistribution of N and Si occurs on the borders of nanograins after annealing, amorphous phase α-SiNx (Si3N4) is created, defects segregates on interfaces and forms vacancy-type clusters with rather high concentration from 5 × 1016 cm-3 to 7.5 × 1017 cm-3 due to thermodiffusion. Solid solution (Ti,Si)N and small concentration of α-SiN (close to XRD detection limits) are formed in the coating. Also it was obtained, that deflected mode is formed in the coating (compressive deformation equals to –2.6%), but after thermal annealing deformation reduces to a value of -2.3%. Size of nanograins of solid solution (Ti, Si)N increases from 12.5 nm to (13.2 ÷ 13.4) nm. 25 nm size grains increase their size to 28.5 nm after annealing (under another deposition regime).
Anamika Sharma, Rakesh Kumar Sharma
Soft Nanoscience Letters, Volume 3, pp 1-5; doi:10.4236/snl.2013.34a001

Abstract:
Intentional release of pathogens or biotoxin against humans, plants, or animals is an impending threat all over the world. Continuous monitoring of environment is required for their detection. These signals can help to distinguish whether the bioattack has occurred or not. Biosensors utilise biological response including different biochemical reactions, antigen antibody reactions, electrochemical reactions, aptameric reactions etc. The currently available biosensors have a limit of detection, specificity and less linearity which affect their sensitivity. Aptamers are single stranded oligonucleotides binding species which are capable of tightly binding to their distinguishing targets. They are evolved from random oligonucleotides pools by using different strategies. These are capable of conscientiously distinguishing their target ligands. They have high sensitivity and a wide range of detection limit. The versatility of nucleic acid based methods allowed for the design of specific aptamer sequences, typically on the order of 10 to 30 base pairs in length, identifying the different biothreat agents in the environment. By using different bioinformatics tools we can design RNA aptamers for toxins of lectin family.
Ngangbam Bedamani Singh, Barnali Bhattacharya,
Soft Nanoscience Letters, Volume 3, pp 9-11; doi:10.4236/snl.2013.34a003

Abstract:
Based on spin-polarized density functional theory (DFT) calculations, the interaction between nickel cluster decorated single-wall carbon nanotube (CNT) and CO molecule has been investigated. DFT calculations are performed with generalized gradient approximation (GGA) using Perdew-Burke-Ernzerhof (PBE) functional. Interaction of CNT and cluster induces spin polarization in the CNT. Nickel decorated CNT has a large magnetic moment of 4.00 μB which decreases to 0.10 μB when CO molecule is absorbed to it. Such a drastic reduction in magnetization may be detected by SQUID magnetometer. Hence by measuring magnetization change, CNT-cluster system may be used as gas detectors. The charge transfer between the systems has been discussed through Mulliken charge analysis for different orientations of the adsorbed CO molecule. We observed that CNT-cluster system acts as electron donor and CO molecule acts as electron acceptor in this study.
Dipankar Chakravorty, Bhola Nath Pal, Shilpi Banerjee, Amrita Mandal, , Dhriti Ranjan Saha
Soft Nanoscience Letters, Volume 3, pp 12-15; doi:10.4236/snl.2013.34a004

Abstract:
Silver nanoparticles of diameters 3.4 to 13.2 nm grown at the interfaces between silicate glass and some oxide crystallites exhibited about six orders of magnitude reduction in resistivity for a relative humidity change from 25% to 80%. Sn-SnO2 nano core-shell structure prepared within a gel-derived silica glass film by electrodeposition technique followed by heat treatment showed large change in resistivity as a function of humidity. The resistivity also changed due to gas flow of CO2, C2H5OH and NO2, respectively. The latter arose because of reduction/oxidation of Sn4+/Sn2+ species present at the shell layer of the nanostructures. Nickel nanosheets of thickness ~0.6 nm grown within the interlayer spaces of Na-4 mica crystallites showed a change of dielectric permittivity (5%) for an applied magnetic field of 1.2 Tesla. An inhomogeneous model was used to explain this behavior. Two dimensional CuO phase was grown within the channels of diameter ~5 nm of mesoporous SiO2 structure. A magnetodielectric (MD) parameter M.D. of 4.4% was obtained in this case. BaTiO3 nanoparticles of diameter ~25 nm having pores with diameter 10 nm showed multiferroic behavior which arose due to the presence of oxygen vacancies as a result of large surface area present. An M.D. parameter of 11% was found. Similarly mesoporous LiNbO3 of 10 nm diameter showed an M.D. parameter of ~4.5% at a magnetic field 1 Tesla. A giant magnetocapacitance effect with a value of 44% at 1.5 T was observed in nickel zinc ferrite (NZF) impregnated mesoporous silica. A magnetocapacitance of 51% at magnetic field 1.7 T was found in the case of nanocomposites comprising of iron ion containing silica based nanoglass and mesoporous silica. In the last two examples the behavior was explained on the basis of Catalan model of space-charge polarization with extracted values of magnetoresistance of the NZF and nanoglass phases being 58%.
, Sachindra Nath Sarangi, Kazuo Uchida, Surendra N. Sahu
Soft Nanoscience Letters, Volume 3, pp 23-26; doi:10.4236/snl.2013.34a007

Abstract:
High-quality zinc oxide nanorods were grown on various substrates using zinc nitrate (Zn(NO3)2) and hexamethylenetetramine ((CH2)6N4). The substrates greatly affect the hydrothermal growth of ZnO nanorods. Making the best use the substrate effect, we engineered substrates to make a single nanorod in each hole of 100 nm × 100 nm in the array of the holes on the photoresist-patterned substrate. It is also interesting to note that high-quality ZnO nanorods grown on GaN substrates by the hydrothermal growth technique have demonstrated the potential application as a glucose sensor without oxidase for the first time. The photoluminescence in the UV wavelength range was quenched by immobilizing glucose on the ZnO surface. The peak intensity decreased increased with the increased glucose concentrations. A good linearity and high sensitivity were obtained for the glucose concentrations of 0.5-30 mM in the calibration curve. The calibration curve was not influenced by the presence of bovin serum albumin (BSA), ascorbic acid (AA) and uric acid (UA), which are also included in human blood and could cause interference in estimating glucose concentrations in human blood. The PL quenching was attributed to the H2O2 molecules, which were produced by the photo-oxidation of glucose during exposure to UV light. The PL-quenching glucose sensor made of ZnO nanorods has been evaluated for the first time by estimating the glucose concentrations in the human serum samples which include those of diabetes, and a good correlation was obtained between the concentrations by the PL quenching and the clinical data provided by a local hospital.
Pradyumna Mulpur, Sandeep Patnaik, L A Avinash Chunduri, Tanu Mimani Rattan, , Venkataramaniah Kamisetti
Soft Nanoscience Letters, Volume 3, pp 27-31; doi:10.4236/snl.2013.34a008

Abstract:
We report the first time fabrication of a silver-α nano alumina thin film hybrid and the observation of the Surface Plasmon Coupled Emission (SPCE) phenomenon in these substrates. We report an “8” fold enhancement in the intensity of the coupled emission signal with respect to the isotropic fluorescence signal. The coupled emission signal displayed a strong p-polarized (92%, p-polarized) output and directionality, which is in accordance with the theory of SPCE. The directionality of emission was found to have strong correlation with the theoretical modeling of minimum reflectivity calculations based on the theory of Surface Plasmon Resonance (SPR). We also report the novel extension of the fabricated substrates towards the economical and sensitive detection of toxic Cd2+ ions from aqueous solutions, which are of immense social relevance.
S. Ramakanth, K. C. James Raju
Soft Nanoscience Letters, Volume 3, pp 32-35; doi:10.4236/snl.2013.34a009

Abstract:
Two sets of gold nanoparticles (NP) embedded in amorphous BaTiO3 films were prepared by sol-gel method using spin coating. Sample (1) is having BaTiO3 sol with 0.025 gm of Chloroauric acid dissolved in 10 ml of propan-2-ol, while sample (2) is having 0.086 gm of Chloroauric acid in the same amount of propan-2-ol. The films have been deposited on various substrates like borosilicate glass and fused silica. TEM images show that the particles are of 5 and 10 nm in size for the two set of samples, and some are having elongated morphology. Optical absorption properties of these films reveal the substrate and size effect on localised surface plasmon resonance (SPR). It shows a marginal red shift in the plasmon resonance peak from 414 nm to 420 nm in the case of sample (1) and 566 nm to 568 nm for sample (2) as the substrate changed from borosilicate glass to fused silica. It also shows red shift in Plasmon peak as the size increases from 5 to 10 nm and coincides with Mie explanation for the shift with size.
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