ISRN Nanotechnology http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. TiO2 Microwave Synthesis, Electrophoretic Deposition of Thin Film, and Photocatalytic Properties for Methylene Blue and Methyl Red Dyes Mon, 07 Apr 2014 15:38:49 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2014/326747/ Electrophoretic deposition (EPD) of TiO2 thin film was carried out at room temperature on low cost steel substrate using microwave synthesized nanoparticles (NPs) of TiO2. Synthesized NPs and EPD thin film were characterized at different stages of synthesis for its crystal structure, morphology, elemental analysis, and surface area. Spherical particle morphology and formation of TiO2 were confirmed by scanning electron micrograph (SEM), energy dispersive spectrometer (EDS), and X-ray diffraction (XRD). Synthesized NPs were formed in anatase phase having crystallite size of about 12.3 nm from Scherrer's formula using full width half maxima (FWHM). Surface area was found to be 43.52 m2/g by BET giving particle size of 33 nm. Photocatalytic (PC) behavior of TiO2 NPs and EPD TiO2 film on steel substrate was investigated under UV light for two commercial dyes and their photocatalysis efficiency was analyzed. NPs have shown better efficiency for methylene blue (MB) dye than EPD film whereas EPD film have shown higher PC activity for methyl red (MR) dye. A. K. Singh and Umesh T. Nakate Copyright © 2014 A. K. Singh and Umesh T. Nakate. All rights reserved. Treatment of Anemia Progression via Magnetite and Folate Nanoparticles In Vivo Tue, 04 Mar 2014 08:15:34 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2014/287575/ Iron deficiency anemia is a major global public health problem. Food fortification with iron (Fe) can be an effective strategy to control iron deficiency. An iron oxide nanoparticle (NP) is a new physical and chemical property form. These properties (small particle size, unique physical properties) make nanoiron a great scientific interest especially in the treatment of anemia. The study aimed to reduce anemia by nanoparticles (NPs). Forty-eight adult female Sprague-Dewily rats were divided into four groups (12 rats each). Group A represented a negative control. Other groups were fed standard diet iron free and three time of require zinc to reach anemic. Group B fed standard diet with ferrous sulfate until the improvement of the situation of anemia or for 8 weeks. Groups C and D were divided into three subgroups; each subgroup was fed a dose from magnetite or folate coated magnetite NPs. Results showed that symptoms of loss of appetite and severe lethargy demonstrate that magnetite and folate-coated magnetite nanoparticles have serious toxicological effects in vivo. Some doses from NPs improve blood picture during 2 weeks but change in histopathology examinations were occur in some groups within 2 weeks. Nanoparticles were considered the toxicological hazards especially the size of less than 54 nm. Hanaa Hussein Elsayed, Al Sayed A. M. Al-Sherbini, Eman Elsayed Abd-Elhady, and Kawkab Abd El Aziz. Ahmed Copyright © 2014 Hanaa Hussein Elsayed et al. All rights reserved. Heterogeneous Catalysis of C–O Bond Cleavage for Cellulose Deconstruction: A Potential Pathway for Ethanol Production Thu, 20 Feb 2014 07:06:16 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2014/634679/ Due to difficulty deconstructing the linkages between lignin, hemicellulose and cellulose during the conversion of cellulose to sugar, the commercial production of cellulosic ethanol is limited. This can be overcome by using a high surface-area metal catalyst. In this study, high surface-area metal NPs were synthesized using 20 mM of chloroplatinic acid and cobalt chloride prepared in THF with 0.1 mM of generation four poly(amido)amine (PAMAM) terminated dendrimer (G4-NH2) prepared in methanol and stirred for 2 hours under nitrogen. Subsequently, Pt+2 and Co+2 ions were reduced to metal zero via introduction of sodium borohydride and centrifuged for complete separation. The resulting product was heated for 2.5 hours at ~200°C. After cooling, 2.0 grams of crushed peanut shells was added to 40 mL of distilled tert-butyl methyl ether along with the separated metal nanocatalyst and refluxed on condenser at 20% for 24 hours. UV-Vis and XRD analyses show the formation of Pt and Co nanoparticles using dendrimer templating methodology. Both TLC and HPLC show that, upon introduction of the metal catalyst into the suspension of “cellulose” in TBME, separation of the cellulose into small molecules is evident. That is, release of sugar molecules via C–O bond cleavage is facilitated by the formed nanocatalysts. Kristy Crews, Crystal Reeves, Porsha Thomas, Daniel Abugri, Albert Russell, and Michael L. Curry Copyright © 2014 Kristy Crews et al. All rights reserved. Factorial Design Studies and Biopharmaceutical Evaluation of Simvastatin Loaded Solid Lipid Nanoparticles for Improving the Oral Bioavailability Thu, 13 Feb 2014 00:00:00 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2014/951016/ Statins are HMG-CoA reductase inhibitors, which lower the cholesterol level through reversible and competitive inhibition; they are involved in the biosynthesis of cholesterol and other sterols. Simvastatin exhibits poor oral bioavailability (<5%) and undergoes extensive microsomal metabolism by CYP enzymes. CYP3A4 is the major metabolizing enzyme that metabolizes lactone form of simvastatin and significantly lowers intestinal uptake. The hydrophobic properties of simvastatin prevent complete dissolution of the drug in the intestinal fluid which also contributes to its lower bioavailability. SLNs are alternative carrier system to polymeric nanoparticles. SLNs are in submicron size range (1–1000 nm). To overcome the hepatic first pass metabolism and to enhance the bioavailability, intestinal lymphatic transport of drugs can be exploited. In the present study, attempt has been made to prepare solid lipid nanoparticles of simvastatin to improve the bioavailability. SLNs of simvastatin were prepared with Trimyristin by hot homogenization followed by ultrasonication method. The SLNs were characterized for various physicochemical properties and analytical techniques like PXRD, DSC to study thermal nature and morphology of formulation and excipients. Promising results of the study indicated the applicability of simvastatin solid lipid nanoparticles as potential tools for improvement of bioavailability of poorly soluble drugs. Kovoru Krishnam Raju, Beeravelli Sudhakar, and Kolapalli Venkata Ramana Murthy Copyright © 2014 Kovoru Krishnam Raju et al. All rights reserved. Silver Nanoparticle Synthesis Using Monosaccharides and Their Growth Inhibitory Activity against Gram-Negative and Positive Bacteria Wed, 12 Feb 2014 11:12:29 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2014/480284/ Using various monosaccharides as reductant, we synthesized Ag nanoparticles (NPs) in seconds employing the household microwave method described earlier. The Ag NPs containing colloidal solution showed distinctive colors with varying . The sizes of the NPs formed varied significantly from 10 to 35 nm in good agreement with the localized plasmon resonance ranged from ~300 to ~600 nm. The antimicrobial properties of these NPs were compared in Gram-negative and positive bacteria in liquid culture. Gram-positive bacteria were highly susceptible compared to Gram-negative microbes—the additional lipopolysaccharide layer covering the peptidoglycan cell wall in the latter somewhat lessens the effect. The results indicated that larger NPs produced by glucose inhibited bacterial growth better than the smallest NPs produced by ribose. This may be attributed to the higher aggregation rate for larger NPs on cell wall. SEM analysis showed accumulation of NPs on cell surface and defect in budding, further supporting the cell wall interaction with Ag NPs. These observations suggested that the growth inhibition of Ag NPs is mediated by interfering with the bacterial cell wall peptidoglycan. Colin Pettegrew, Zheng Dong, M. Zubayed Muhi, Scott Pease, M. Abdul Mottaleb, and M. Rafiq Islam Copyright © 2014 Colin Pettegrew et al. All rights reserved. Structural and Magnetic Properties of Microwave Assisted Sol-Gel Synthesized Manganite Nanoparticles Mon, 10 Feb 2014 11:37:08 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2014/867139/ The structural and magnetic properties of nanoparticles of (LSMO) were studied using powder X-ray diffraction (XRD), transmission electron microscope (TEM), and magnetic measurements. The XRD refinement result indicates that samples crystallize in the rhombohedral structure with R-3C space group. The dc magnetization measurements revealed that samples exhibit no hysteretic behavior at room temperature, symptomatic of the superparamagnetic (SPM) behavior. The results of ac magnetic susceptibility measurements show that the susceptibility data are not in accordance with the Néel-Brown model for SPM relaxation but fit well with conventional critical slowing down model which indicates that the dipole-dipole interactions are strong enough to cause superspin-glass-like phase in LSMO samples. Mahin Eshraghi and Parviz Kameli Copyright © 2014 Mahin Eshraghi and Parviz Kameli. All rights reserved. Silver Nanoparticles: Green Synthesis, Characterization, and Their Usage in Determination of Mercury Contamination in Seafoods Tue, 04 Feb 2014 07:18:45 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2014/148184/ We demonstrate that silver nanoparticles undergo an interaction with Hg2+ found in traces. The PEG-PVP-stabilized Ag nanoparticles were successfully synthesized via a reduction approach and characterized with surface plasmon resonance UV/Vis spectroscopy. By utilizing the redox reaction between Ag nanoparticles and Hg2+, and the resulted decrease in UV/Vis signal, we develop a colorimetric method for detection of Hg2+ ion. A linear and inversely proportional relationship was found between the absorbance intensity of the Ag nanoparticles and the concentration of Hg2+ ion over the range from 10 ppm to 1 ppm at absorption on 411 nm. The detection limit for Hg2+ ions in homogeneous aqueous solutions is estimated to be 1 ppm. This system shows excellent selectivity for Hg2+. The results found have potential implications in the development of new colorimetric sensors for easy and selective detection and monitoring of mercuric ions in aqueous solutions. The proposed method was successfully applied to quantify the amount of mercury in seafood. Muhammad Ahad Ahmed, Najmul Hasan, and Shaikh Mohiuddin Copyright © 2014 Muhammad Ahad Ahmed et al. All rights reserved. Biosynthesis of Self-Dispersed Silver Colloidal Particles Using the Aqueous Extract of P. peruviana for Sensing dl-Alanine Sun, 02 Feb 2014 08:17:21 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2014/670780/ We report the biosynthesis of silver nanoparticles (AgNPs) in a single step using edible fruit aqueous extract of P. peruviana that essentially involved the concept of green chemistry. Yellowish-brown color appeared upon adding the broth of P. peruviana to aqueous solution of 1 mM AgNO3 which indicates the formation of AgNPs. The maximum synthesis of these nanoparticles was being achieved in nearly 2 hrs at 28°C. The synthesis of AgNPs was followed by AgNPs UV-visible spectroscopy. Particle size and morphology of AgNPs were studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), respectively. These studies revealed that the AgNPs characterized were spherical in shape with diameter ranging from 31 to 52 nm. The energy dispersive X-ray spectroscopy showed that the AgNPs present are approximately 63.42 percent by weight in the colloidal dispersion. The absorption spectra of the AgNPs in absence and presence of dl-alanine show a distinguish shift in surface plasmon resonance (SPR) bands. Thus, these nanoparticles may be used as a chemical sensor for dl-alanine present in the human blood. Mohd Rashid and Suhail Sabir Copyright © 2014 Mohd Rashid and Suhail Sabir. All rights reserved. Nanotechnology in Cancer Drug Delivery and Selective Targeting Thu, 16 Jan 2014 11:45:33 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2014/939378/ Nanoparticles are rapidly being developed and trialed to overcome several limitations of traditional drug delivery systems and are coming up as a distinct therapeutics for cancer treatment. Conventional chemotherapeutics possess some serious side effects including damage of the immune system and other organs with rapidly proliferating cells due to nonspecific targeting, lack of solubility, and inability to enter the core of the tumors resulting in impaired treatment with reduced dose and with low survival rate. Nanotechnology has provided the opportunity to get direct access of the cancerous cells selectively with increased drug localization and cellular uptake. Nanoparticles can be programmed for recognizing the cancerous cells and giving selective and accurate drug delivery avoiding interaction with the healthy cells. This review focuses on cell recognizing ability of nanoparticles by various strategies having unique identifying properties that distinguish them from previous anticancer therapies. It also discusses specific drug delivery by nanoparticles inside the cells illustrating many successful researches and how nanoparticles remove the side effects of conventional therapies with tailored cancer treatment. Kumar Bishwajit Sutradhar and Md. Lutful Amin Copyright © 2014 Kumar Bishwajit Sutradhar and Md. Lutful Amin. All rights reserved. Synthesis and Characterization of Electrophoretically Deposited Nanostructured LiCoPO4 for Rechargeable Lithium Ion Batteries Tue, 17 Dec 2013 15:09:55 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/653237/ Nanosized LiCoPO4 (LCP) was prepared using a simple sol-gel method. For the first time, electrophoretic deposition process was employed to fabricate a LiCoPO4 cathode material in order to improve the electrochemical performance. The prepared powder was deposited on titanium plate by electrophoretic deposition and their electrochemical properties were studied. The electrochemical properties were analyzed by using cyclic voltagramm studies, impedance studies, and charge/discharge tests. The thickness of the prepared cathode material was found to be 11-12 µm by using scanning electron microscope. The initial specific capacity and the charge transfer resistance (Rct) of the prepared cathode was 103 mAh/g and 851 Ω, respectively. The charge/discharge profiles showed moderate columbic efficiency of 70%. S. Priya Nair, U. Jyothsna, P. Praveen, A. Balakrishnan, K. R. V. Subramanian, Shantikumar V. Nair, and N. Sivakumar Copyright © 2013 S. Priya Nair et al. All rights reserved. Synthesis and Optical Characterization of Sulfonated Polyaniline/Single-Walled Carbon Nanotube/Zinc Sulphide Nanocomposite Mon, 04 Nov 2013 09:40:59 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/253016/ Polyaniline functionalized with sulfonate groups (SPANI) shows excellent solubility in water. Single-walled carbon nanotubes functionalized with carboxylic groups (f-SWCNTs) and then hybridized with freshly prepared zinc sulphide (ZnS) nanocrystals have been found to be good luminescent material with tuned emission properties. Nanocomposite of sulfonated polyaniline with embedded SWCNT/ZnS nanohybrid fibers has been prepared by a simple solution mixing process and characterized by using high resolution transmission electron microscopy (HRTEM), X-ray diffractometry, Raman spectroscopy, FTIR spectroscopy, and thermogravimetric analysis (TGA). The study of optical properties by UV-vis absorption and photoluminescence spectroscopy reveals that the composite is a luminescent material of enhanced emission intensity in the visible region of the spectrum. Rajesh K. Agrawalla, Rima Paul, Amit K. Chakraborty, and Apurba K. Mitra Copyright © 2013 Rajesh K. Agrawalla et al. All rights reserved. Electrochemical Response for Spherical and Rod Shaped WO3 Nanoparticles Wed, 23 Oct 2013 10:11:08 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/279398/ A rapid and new technique describes synthesis technique of spherical and rod shaped tungsten trioxide (WO3) nanoparticles with similar band gap at visible wavelength. Acid catalyzed exothermic reaction and structure directing reagent follows the formation of two different morphologies and monoclinic WO3 phase. Rod shaped WO3 nanoparticle coated ITO glass electrode exhibits high current density at identical low voltage and scan rate due to its better adherence and coating uniformity in comparison with spherical nanoparticles. WO3-ITO electrode alters to blue tungsten bronze in color at low voltage, and further the color restores after removing the same applied voltage. Sangeeta Adhikari and Debasish Sarkar Copyright © 2013 Sangeeta Adhikari and Debasish Sarkar. All rights reserved. Numerical Solution of MHD Viscoelastic Nanofluid Flow over a Stretching Sheet with Partial Slip and Heat Source/Sink Thu, 19 Sep 2013 14:25:33 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/931021/ We analyze the effect of velocity slip boundary condition on the flow and heat transfer of non-Newtonian nanofluid over a stretching sheet with a heat source/sink, under the action of a uniform magnetic field, orientated normally to the plate. The Brownian motion and thermophoresis effects are also considered. The boundary layer equations governed by the partial differential equations are transformed into a set of ordinary differential equations with the help of local similarity transformations. The differential equations are solved by the variational finite element method (FEM). We have examined the effects of different controlling parameters, namely, the Brownian motion parameter, the thermophoresis parameter, uniform magnetic field, viscoelastic parameter, Prandtl number, heat source/sink parameter, Lewis number, and the slip parameter on the flow field and heat transfer characteristics. Graphical display of the numerical examination is performed to illustrate the influence of various flow parameters on the velocity, temperature, concentration, and Nusselt and Sherwood numbers distributions. The present study has many applications in coating and suspensions, cooling of metallic plate, paper production, heat exchangers technology, and materials processing exploiting. Mania Goyal and Rama Bhargava Copyright © 2013 Mania Goyal and Rama Bhargava. All rights reserved. Comparative Study on the Synergistic Action of Garlic Synthesized and Citrate Capped Silver Nanoparticles with β-Penem Antibiotics Sun, 15 Sep 2013 13:34:02 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/792105/ Resistance to antimicrobial agents by pathogenic bacteria has emerged in recent years and is a major challenge for the health care industry. For developing a cheap broad-active agent that can be applicable against different pathogens, it is necessary to develop an alternative source for normal antibacterial agents. This paper mainly focuses on the combined action of green as well as citrate synthesized silver nanoparticles and β-penem antibiotics, which are β-lactam antibiotics with penem rings. These silver nanoparticles synergistic potential helps in the enhancement of antibacterial activity of broad spectrum antibiotics. The synergistic actions of citrate capped silver nanoparticles (Ag-NPs) were compared with that of garlic (Allium sativum) synthesized silver nanoparticles together with action of antibiotics, ampicillin and amoxyclav, and some of the pathogenic organisms showed an increase in the action of antibiotics. Neethu Hari, Tincy K. Thomas, and A. Jayakumaran Nair Copyright © 2013 Neethu Hari et al. All rights reserved. Sol-Gel Synthesis and Structural Characterization of Nano-Thiamine Hydrochloride Structure Tue, 10 Sep 2013 10:44:37 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/815071/ The study presents the synthesis of nano-thiamine hydrochloride structure (NTH) using sol-gel method by hydrolysis of tetraethyl orthosilicate with ethanol and water mixture as silica source and nitric acid as catalyst support in which thiamine hydrochloride nanocrystals were dispersed in the silica glassy matrix. The synthesized nanocomposite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The morphological observation of the SEM results reveals that the nano-thiamine hydrochloride composites are in the range of 5–15 nm in size. Salameh Azimi Copyright © 2013 Salameh Azimi. All rights reserved. Design of a Single-Electron Memory Operating at Room Temperature Thu, 22 Aug 2013 09:50:02 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/587436/ Single-electronic transistors (SETs) are considered as the attractive component for the next generation of transistors due to their ultrasmall size and low power consumption. Because SETs with single island cannot work at high temperature normally, more researchers begin to carry out research on the SETs with N-dimension multi-islands. In this paper, we introduce a new architecture of single-electron memory; ideally the memory should operate in combination of SETs with a nanowire of two-dimensional regular array of multiple tunnel junctions (MTJs). This structure is analyzed and studied with Monte Carlo simulator, SIMON. The Coulomb blockade effect and thermionic effect play an important role in carrier conduction in the system at room temperature. Nanowire MTJs are used as an electrometer to sense the memory-node charge. The well-defined parameter in tunnel junction circuits helps to obtain the charging of single electrons in these circuits at room temperature. Amine Touati, Samir Chatbouri, and Kalboussi Adel Copyright © 2013 Amine Touati et al. All rights reserved. Targeted, Monitored, and Controlled Chemotherapy: A Multimodal Nanotechnology-Based Approach against Cancer Wed, 21 Aug 2013 12:02:06 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/629510/ We review innovative methods for treatment of cancer tumor on the basis of nanotechnology and physics to target, monitor and control release of chemotherapeutic agents. Chemotherapy is one of the main methods of treatment for cancer and plays a vital role in clinical practice, but side effects of anticancer drugs are still critical problems. Magnetic nanoparticles can be applied as an effective drug carriers and contrast agents for magnetic resonance imaging (MRI). Since certain nanoparticles have magnetic properties, they can be trapped in tumor during blood circulation by an external magnetic field. Also, polymeric nanoparticles are great candidates to encapsulate anticancer drugs and to control the release profile of drugs in biologic media. We suggest the construction of drug-loaded polymer-coated magnetic (DPM) nanoplatform with the potential for being utilized in medical imaging as well as having controlled drug release properties. Nanoplatform distribution can be monitored by MRI and with clever combination of ultrasound physics and suggested DPM nanoplatform, it would be feasible to increase the rate of drug release (in situ) and drug uptake by cancerous cell. To optimize the level of drug uptake by cancerous cell, the selection of ultrasound frequency and intensity is essential. The development of suggested method could be a new approach against cancer tumor. Ali Shakeri-Zadeh, Samideh Khoei, Sepideh Khoee, Ali Mohammad Sharifi, and Mohammad-Bagher Shiran Copyright © 2013 Ali Shakeri-Zadeh et al. All rights reserved. Experimental Investigation of Thermal Conductivity and Effusivity of Ferrite Based Nanofluids under Magnetic Field Sun, 04 Aug 2013 11:58:29 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/479763/ We investigate the effect of magnetic field () on the thermal conductivity () and effusivity () of cobalt ferrite based nanofluids having different concentrations (). Cobalt ferrite nanoparticles (NPs) have been synthesized using the microwave assisted method. At high volume fraction of cobalt ferrite nanoparticles in water ( > 0), both thermal parameters have been found to be suppressed relative to and of water in the absence of . However, it is seen that percentage values of the effusivity in perpendicular field direction show negative to positive variation, and thermal conductivity in parallel field direction shows negative to zero variation. Ashok K. Singh and Vijay S. Raykar Copyright © 2013 Ashok K. Singh and Vijay S. Raykar. All rights reserved. Catalytic Sorption of (Chloro)Benzene and Naphthalene in Aqueous Solutions by Granular Activated Carbon Supported Bimetallic Iron and Palladium Nanoparticles Sun, 28 Jul 2013 14:23:47 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/525697/ Adsorption of benzene, chlorobenzene, and naphthalene on commercially available granular activated carbon (GAC) and bimetallic nanoparticle (Fe/Pd) loaded GAC was investigated for the potential use in active capping of contaminated sediments. Freundlich and Langmuir linearizations were both applied to this data, and it was found that the Freundlich model most closely fits the experimental data. Based on Freundlich parameters, the effective partitioning coefficients (L kg−1) taking into account and were calculated to be and for benzene and chlorobenzene, respectively, on GAC. In addition, effective partitioning coefficients (L kg−1) were 650, 5640, and for benzene, chlorobenzene, and naphthalene, respectively, on Fe/Pd/GAC. Values of were 6.11, 7.11, and 7.54 for benzene, chlorobenzene, and naphthalene, respectively, for GAC and 4.53, 5.47, and 5.22, respectively, for Fe/Pd/GAC. Jurate Virkutyte, Souhail R. Al-Abed, Edwin F. Barth, Danny Reible, Patrick Dunlap, and Sandip Chattopadhyay Copyright © 2013 Jurate Virkutyte et al. All rights reserved. Microscopic Studies of Various Sizes of Gold Nanoparticles and Their Cellular Localizations Sun, 28 Jul 2013 10:18:59 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/123838/ Gold nanoparticles (GNPs) are widely used in biological and clinical applications due to their favorable chemical and optical properties. GNPs can be used for drug delivery to targeted cells. In addition, GNPs serve as ideal probes for biological and cell imaging applications. Recent studies indicate that the size diversity of GNPs plays an important role in targeting cellular components for biomedical applications. In this study, we conducted a series of studies using different sizes of gold nanoparticles, including 3, 10, 25, and 50 nm, to determine the effect of size variations on their intracellular localizations. Our cytotoxicity studies of GNPs into the HEp-2 cells using MTT assay indicated that 3 nm GNPs possess the highest toxicity. We exposed HEp-2 cells with various sizes of gold nanoparticles for different time intervals (1, 2, 4, 12, and 24 h) followed by imaging using scanning electron microscope (SEM) and atomic force microscope (AFM). Our SEM and AFM results showed that, after 1 hr incubation, 3 and 10 nm gold nanoparticles entered the nucleus, whereas 25 and 50 nm particles accumulated around the nucleus. As the time of exposure increased, GNPs entered the cells and accumulated in the cytosol and nucleus based solely on their sizes. Cemil Boyoglu, Qingwen He, Gerold Willing, Seyhan Boyoglu-Barnum, Vida A. Dennis, Shreekumar Pillai, and Shree R. Singh Copyright © 2013 Cemil Boyoglu et al. All rights reserved. Resolution Improvement in Stage-Scanning Electron Holography: Comparison with Conventional Electron Holography Sun, 21 Jul 2013 11:49:49 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/368671/ Electron holography provides information on the phase and amplitude of electron wave passing through a specimen. The recently proposed stage-scanning electron holography technique should improve the spatial resolution of phase and amplitude images compared to the conventional electron holography based on the Fourier transformation method. To demonstrate the resolution improvement, cobalt nanoparticles were observed using the stage-scanning holography and the conventional holography, and significantly sharper images were obtained with the former technique. Dan Lei, Kazutaka Mitsuishi, Ken Harada, Masayuki Shimojo, Dongying Ju, and Masaki Takeguchi Copyright © 2013 Dan Lei et al. All rights reserved. Development and Evaluation of Insulin Incorporated Nanoparticles for Oral Administration Mon, 15 Jul 2013 11:27:11 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/591751/ The current study was designed to prepare and characterize insulin incorporated nanoparticles by complex coacervation process followed by antidiabetic study of orally administered insulin incorporated nanoparticles in diabetic rats. The nanoparticles were characterized for particle size, loading and entrapment efficiency as well as in vitro release of incorporated insulin. The prepared nanoparticles were found to have an average particle size of 551.67 nm . The highest entrapment efficiency and loading capacity values were found to be of and , respectively. Oral administration of 10 IU/Kg of insulin loaded nanoparticles to diabetic rats showed a maximum blood glucose change of at 5-hours time period. The results obtained indicate the potential of prepared nanoparticulate system as a carrier for oral delivery of insulin. Amiya kumar Prusty and Susanta Kumar Sahu Copyright © 2013 Amiya kumar Prusty and Susanta Kumar Sahu. All rights reserved. Amino-Functionalization of Multiwall Carbon Nanotubes and Its Use for Solid Phase Extraction of Mercury Ions from Fish Sample Thu, 20 Jun 2013 17:14:24 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/674289/ We describe here the amino-functionalization of multiwall carbon nanotubes (MWCNTs) and also its application as an adsorbent of solid phase extraction (SPE). The amino-functionalized MWCNTs have a good capacity to retain Hg2+, but the raw and purified MWCNTs are found not to adsorb Hg2+ ions. The amino-functionalized MWCNTs are prepared with amino-functionalization of purified MWCNTs by ethylenediamine. The physicochemical properties of purified and amino-functionalized MWCNTs are characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and the Boehm titration. The amino-functionalized MWCNTs are selected as novel sorbents for the solid phase extraction of Hg2+. The amino-functionalized MWCNT-SPE method is used for the determination of Hg2+ from complex matrix including fish and real water samples. Effective parameters on Hg2+ retention such as pH, flowrate, nature of the eluent, the ionic strength, selectivity coefficient, and retention capacity are investigated. The enrichment factor and maximum capacity of the sorbent are 100 mL and 11.58 mg/g, respectively. The linear range, limit of detection, and relative standard deviation of the proposed method are 0.003 to 0.3 μg/L,  μg/L, and 2.23%, respectively. Selectivity experiments show that the adsorbents have a stronger specific retention for Hg2+ than Fe3+, Cu2+, Pb2+, Ni2+, Mn2+, Ca2+, and Mg2+. Majid Soleimani, Majid Ghahraman Afshar, and Arman Sedghi Copyright © 2013 Majid Soleimani et al. All rights reserved. High Pressure Equation of State for Nanomaterials Mon, 17 Jun 2013 18:52:32 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/404920/ Shanker Equation of State is used to study the volume compression of nanocrystalline materials under different pressure. On comparing with the experimental data it gives good results at low pressure, but for higher compression it deviates from the experimental points. Therefore, the Equation of State is modified empirically to study the pressure-volume relation for nanomaterials, namely, n-Rb3C60, n-CdSe (rocksalt phase), n-TiO2 (anatase and rutile phase), Fe-filled nanotube, and γ-Fe2O3, at high pressure. The results obtained from the empirical Equation of State are found to be in better agreement with the available experimental data. Jeewan C. Bhatt, Kuldeep Kholiya, and Ravindra Kumar Copyright © 2013 Jeewan C. Bhatt et al. All rights reserved. Potentiostatic Deposition and Characterization of Cuprous Oxide Thin Films Wed, 17 Apr 2013 16:34:17 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/271545/ Electrodeposition technique was employed to deposit cuprous oxide Cu2O thin films. In this work, Cu2O thin films have been grown on fluorine doped tin oxide (FTO) transparent conducting glass as a substrate by potentiostatic deposition of cupric acetate. The effect of deposition time on the morphologies, crystalline, and optical quality of Cu2O thin films was investigated. A. El-Shaer and A. R. Abdelwahed Copyright © 2013 A. El-Shaer and A. R. Abdelwahed. All rights reserved. Preparation of Gd Complex-Immobilized Silica Particles and Their Application to MRI Wed, 10 Apr 2013 12:02:22 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/908614/ A preparation method for Gd-ethylenediaminetetraacetic acid disodium salt dihydrate (ETDA) complex-immobilized silica particles (Gd-EDTA/SiO2) is proposed. Preparation of spherical silica particles was performed by a sol-gel method at 35°C using 0.2 M tetraethylorthosilicate, 25 M H2O, and 0.01 M NaOH in ethanol, which produced silica particles with an average size of  nm. Immobilization of Gd-EDTA on the silica particles was conducted at 35°C by introducing amino groups on the silica particles with (3-aminopropyl)trimethoxysilane at pH 3 (NH2/SiO2) and then making Gd-EDTA act on the NH2/SiO2 particles at pH 5. The as-prepared Gd-EDTA/SiO2 particle colloid solution was concentrated up to a Gd concentration of 0.347 mM by centrifugation. The sphere structure of Gd-EDTA/SiO2 particles was undamaged, and the colloid solution was still colloidally stable, even after the concentrating process. The concentrated Gd-EDTA/SiO2 colloid solution revealed good MRI properties. A relaxivity value for T1-weighted imaging was as high as 5.15 mM−1 s−1, that was comparable to that for a commercial Gd complex contrast agent. Yoshio Kobayashi, Hikaru Morimoto, Tomohiko Nakagawa, Yohsuke Kubota, Kohsuke Gonda, and Noriaki Ohuchi Copyright © 2013 Yoshio Kobayashi et al. All rights reserved. A Quick Process for Synthesis of ZnO Nanoparticles with the Aid of Microwave Irradiation Wed, 03 Apr 2013 13:36:35 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/497873/ Reaction between sodium hydroxide and zinc acetate leads to the formation of zinc hydroxide, Zn(OH)2. The as-prepared Zn(OH)2 was then decomposed by using conventional heating process or with the aid of microwave irradiation. The nanoproducts of both methods were ZnO nanostructures of different size and shape, but the microwave irradiation method shows many advantages in yield and reaction time. Some surfactants such as SDS, CTAB, or PVP were then used to cap the product for studying the influence on the morphology and properties of the nanostructures. Tran Thi Ha, Ta Dinh Canh, and Nguyen Viet Tuyen Copyright © 2013 Tran Thi Ha et al. All rights reserved. Evaluation of the X-Ray Absorption by Gold Nanoparticles Solutions Mon, 11 Mar 2013 11:19:31 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/865283/ The increase in the X-ray absorption due to gold nanoparticles was investigated by using aqueous solutions containing gold (Au) nanoparticles. A sample with 15 nm in size nanoparticles and 0.5 mg/mL gold concentration and a distilled water sample were used. Transmitted X-ray beams through the samples were registered with a CdTe detector and with an ionization chamber. Results show an enhancement in the X-ray absorption in the range 20%–6% for beams generated from 20 kV to 120 kV tube voltages, respectively. Results show that the use of gold nanoparticles, even at low concentrations, should result in a significant contrast enhancement for low-energy X-ray beams. R. Künzel, E. Okuno, R. S. Levenhagen, and N. K. Umisedo Copyright © 2013 R. Künzel et al. All rights reserved. Ordered Porous Nanomaterials: The Merit of Small Tue, 26 Feb 2013 18:56:13 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/257047/ This paper will introduce the reader to some of the “classical” and “new” families of ordered porous materials which have arisen throughout the past decades and/or years. From what is perhaps the best-known family of zeolites, which even now to this day is under constant research, to the exciting new family of hierarchical porous materials, the number of strategies, structures, porous textures, and potential applications grows with every passing day. We will attempt to put these new families into perspective from a synthetic and applied point of view in order to give the reader as broad a perspective as possible into these exciting materials. Ángel Berenguer Murcia Copyright © 2013 Ángel Berenguer Murcia. All rights reserved. In Situ Real-Time TEM Reveals Growth, Transformation and Function in One-Dimensional Nanoscale Materials: From a Nanotechnology Perspective Sun, 27 Jan 2013 11:03:11 +0000 http://www.hindawi.com/journals/isrn.nanotechnology/2013/893060/ This paper summarises recent developments in in situ TEM instrumentation and operation conditions. The focus of the discussion is on demonstrating how improved understanding of fundamental physical phenomena associated with nanowire or nanotube materials, revealed by following transformations in real time and high resolution, can assist the engineering of emerging electronic and optoelectronic devices. Special attention is given to Si, Ge, and compound semiconductor nanowires and carbon nanotubes (CNTs) as one of the most promising building blocks for devices inspired by nanotechnology. Nikolay Petkov Copyright © 2013 Nikolay Petkov. All rights reserved.