Applied Nanoscience (v.7, #8)

Green synthesis of zinc oxide nanoparticles was carried out using Calotropis leaf extract with zinc acetate salt in the presence of 2 M NaOH. The combination of 200 mM zinc acetate salt and 15 ml of leaf extract was ideal for the synthesis of less than 20 nm size of highly monodisperse crystalline nanoparticles. Synthesized nanoparticles were characterized through UV–Vis spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), EDX (energy dispersive X-ray), and AFM (atomic force microscopy). Effects of biogenic zinc oxide (ZnO) nanoparticles on growth and development of tree seedlings in nursery stage were studied in open-air trenches. The UV–Vis absorption maxima showed peak near 350 nm, which is characteristic of ZnO nanoparticles. DLS data showed that single peak is at 11 nm (100%) and Polydispersity Index is 0.245. XRD analysis showed that these are highly crystalline ZnO nanoparticles having an average size of 10 nm. FTIR spectra were recorded to identify the biomolecules involved in the synthesis process, which showed absorption bands at 4307, 3390, 2825, 871, 439, and 420 cm−1. SEM images showed that the particles were spherical in nature. The presence of zinc and oxygen was confirmed by EDX and the atomic % of zinc and oxygen were 33.31 and 68.69, respectively. 2D and 3D images of ZnO nanoparticles were obtained by AFM studies, which indicated that these are monodisperse having size ranges between 1.5 and 8.5 nm. Significant enhancement of growth was observed in Neem (Azadirachta indica), Karanj (Pongamia pinnata), and Milkwood-pine (Alstonia scholaris) seedlings in foliar spraying ZnO nanoparticles to nursery stage of tree seedlings. Out of the three treated saplings, Alstonia scholaris showed maximum height development.
Keywords: Calotropis leaf; ZnO nanoparticle; DLS; XRD; FTIR; SEM with EDS; AFM; Tree seedling growth

An investigation of effects of bath temperature on CdO films prepared by electrodeposition by Ayça Kıyak Yıldırım; Barış Altıokka (513-518).
CdO thin films were prepared by electrodeposition method. Solution temperatures were varied from 58 to 98 °C. It was understood from the film thicknesses and current densities that the reaction rate increased as the temperature increased. Good crystallization and a thick film were obtained at 98 °C. It was found that the energy band gap varied between 1.99 and 2.61 eV depending on the bath temperature. SEM images also showed that surface morphologies were dependent on bath temperature.
Keywords: CdO; Electrodeposition; Bath temperature; Thin film

Polymer and ceramic nanocomposites for aerospace applications by Vivek T. Rathod; Jayanth S. Kumar; Anjana Jain (519-548).
This paper reviews the potential of polymer and ceramic matrix composites for aerospace/space vehicle applications. Special, unique and multifunctional properties arising due to the dispersion of nanoparticles in ceramic and metal matrix are briefly discussed followed by a classification of resulting aerospace applications. The paper presents polymer matrix composites comprising majority of aerospace applications in structures, coating, tribology, structural health monitoring, electromagnetic shielding and shape memory applications. The capabilities of the ceramic matrix nanocomposites to providing the electromagnetic shielding for aircrafts and better tribological properties to suit space environments are discussed. Structural health monitoring capability of ceramic matrix nanocomposite is also discussed. The properties of resulting nanocomposite material with its disadvantages like cost and processing difficulties are discussed. The paper concludes after the discussion of the possible future perspectives and challenges in implementation and further development of polymer and ceramic nanocomposite materials.
Keywords: Nanocomposite; Aerospace; Tribology; Structural health monitoring; Polymer matrix; Ceramic matrix

Targeted delivery of mesoporous silica nanoparticles loaded monastrol into cancer cells: an in vitro study by Huzaifa Hanif; Samina Nazir; Kehkashan Mazhar; Muhammad Waseem; Shazia Bano; Umer Rashid (549-555).
Monastrol is a simple low molecular weight dihydropyrimidine-based kinesin Eg5 inhibitor. Its low cellular activity and its non-drug-like properties have impeded its further development. In a previous report, we have reported various topological parameters to improve the pharmacokinetic properties of monastrol. The purpose of this study is to determine the loading and release feasibility of poorly water-soluble monastrol into the synthesized mesoporous silica nanoparticles (MSNs). The synthesis of MSNs was attained by the ammonia-catalysed hydrolysis and condensation of TEOS in ethanol using polysorbate-80 as surfactant. These were characterized by BET surface area and pore size distribution analyses, SEM, XRD, UV and FTIR spectroscopy. The synthesized monastrol was successfully loaded on MSNPs and coated by hydrogels for successful controlled drug delivery. In vitro release studies are done by simple dialysis method. Monastrol-loaded MSNPs were tested on human cervical epithelial malignant carcinoma (HeLa) cell lines for studying their anticancer activity. Our presented system described a reliable method for targeted delivery of monastrol into the cancer cells in vitro.
Keywords: Mesoporous silica nanoparticles; Monastrol; KSP; Anticancer; Drug delivery

Green catalyst derived from plants, a cheap and abundant natural source, is used for the synthesis of multi-walled carbon nanotubes (MWNTs). The concept is unconventional and practically realized into existence by simple CVD growth while keeping away the potential hazards caused by metal catalyst on environment and living organisms. The notable points to mention of such growth are: (1) grown CNTs are free from toxic metal catalyst, (2) low growth temperature (575 °C) required and produced high yield vis-à-vis any other catalyst used so far reported, and (3) no need of expensive and complex systems for its synthesis. Besides, growth of SWNT as well as carbon nano-belts with hollow rectangular cross-section is observed when growth temperature increased to 800 °C, specifically, for the wall-nut extract. The samples were characterized by microscopic and spectroscopic analysis and the results verified our study. The present work provides innovative technique and may open up new avenues for CNTs synthesis and its applications.
Keywords: Green catalyst; Low temperature growth; CNTs; CNBs

Here we report the catalytic property of ZnO–CeO2 nanoparticles towards oxidative degradation of organic pollutants present in industrial wastewater. The catalysts were prepared by co-precipitation method without using any surfactant. The physicochemical properties of catalysts were studied by XRD, Raman, XPS, N2-sorption, FE-SEM, TEM and EDX techniques. The characterization results confirmed the formation of porous ZnO–CeO2 nanocatalysts with high surface area, pore volume and oxygen vacancies. ZnO–CeO2 nanocatalysts exhibited appreciable efficiency in CWAO of industrial wastewater under mild conditions. The Ce40Zn60 catalyst was found to be most efficient with 72% color, 64% chemical oxygen demand (COD) and 63% total organic carbon (TOC) removal. Efficient removal of chlorophenolics (CHPs, 59%) and adsorbable organic halides (AOX, 54%) indicated the feasibility of using ZnO–CeO2 nanocatalysts in degradation of non-biodegradable and toxic chlorinated compounds.
Keywords: ZnO–CeO2 ; Catalysis; Porous; Oxygen vacancy; Wet air oxidation

Synthesis, characterization and catalytic activity of nanosized Ni complexed aminoclay by A. Amala Jeya Ranchani; V. Parthasarathy; A. Anitha Devi; B. Meenarathi; R. Anbarasan (577-588).
A novel Ni complexed aminoclay (AC) catalyst was prepared by complexation method followed by reduction reaction. Various analytical techniques such as FTIR spectroscopy, UV–visible spectroscopy, DSC, TGA, SEM, HRTEM, EDX, XPS and WCA measurement are used to characterize the synthesized material. The AC–Ni catalyst system exhibited improved thermal stability and fiber-like morphology. The XPS results declared the formation of Ni nanoparticles. Thus, synthesized catalyst was tested towards the Schiff base formation reaction between various bio-medical polymers and aniline under air atmosphere at 85 °C for 24 h. The catalytic activity of the catalyst was studied by varying the % weight loading of the AC–Ni system towards the Schiff base formation. The Schiff base formation was quantitatively calculated by the 1H-NMR spectroscopy. While increasing the % weight loading of the AC–Ni catalyst, the % yield of Schiff base was also increased. The k app and Ti values were determined for the reduction of indole and α-terpineol in the presence of AC–Ni catalyst system. The experimental results were compared with the literature report.
Keywords: Aminoclay–Ni catalyst; Synthesis and characterization; Schiff base; 1H-NMR spectroscopy; Catalytic reduction

Indium-doped zinc oxide (IZO) nanoparticles (NPs) are produced by pulsed laser ablation in liquid technique. The influence of indium doping on the sizing, structure, morphology and optical properties of nanoparticles was investigated using X-ray diffraction (XRD), transmission electron microscope (TEM), energy dispersive spectrum, UV–Visible and photoluminescence spectroscopies. The XRD results demonstrated that indium-doped ZnO maintained a hexagonal wurtzite structure with a (002) preferential orientation. With reference to the TEM images, the particle size increased with an increase in the doping ratio, and the morphology varied from particle to aggregated spheres and then to NPs. The optical absorption spectra increased with an increase in In-doped concentration, while the band gap had reduced. In addition, the photoluminescence spectrum had a broad green emission from IZO nanoparticles.
Keywords: Laser ablation in liquid; Nanocomposite; IZO nanocolloidal; Indium-doped ZnO materials

Assisted laser ablation: silver/gold nanostructures coated with silica by J. R. González-Castillo; Eugenio Rodríguez-González; Ernesto Jiménez-Villar; Carlos Lenz Cesar; Jacob Antonio Andrade-Arvizu (597-605).
The synthesis processes of metallic nanoparticles have seen a growing interest in recent years, mainly by the potential applications of the phenomenon of localized surface plasmon resonance associated with metallic nanoparticles. This paper shows a fast method to synthesize silver, gold and silver/gold alloy nanoparticles coated with a porous silica shell by the assisted laser ablation method in three steps. The method involves a redox chemical reaction where the reducing agent is supplied in nanometric form by laser ablation. In the first step, a silicon target immersed in water is ablated for several minutes. Later, AgNO3 and HAuCl4 aliquots are added to the solution. The redox reaction between the silver and gold ions and products resulting from ablation process can produce silver, gold or silver/gold alloy nanoparticles coated with a porous silica shell. The influence of the laser pulse energy, ablation time, Ag+ and Au3+ concentration, as well as the Ag+/Au3+ ratio, on optical and structural properties of the nanostructures was investigated. This work represents a step forward in the study of reaction mechanisms that take place during the synthesis of nanoscale materials by the assisted laser ablation technique.
Keywords: Silver/gold nanostructures; Assisted laser ablation; Metallic nanoparticles; Core–shell nanoparticles

Microcarbon-based facial creams activate aerial oxygen under light to reactive oxygen species damaging cell by Sheli Maity; Bholanath Pakhira; Subrata Ghosh; Royina Saha; Ripon Sarkar; Ananya Barui; Sabyasachi Sarkar (607-616).
Nanosized reduced graphene oxide (rGO) is found in active microcarbon used in popular face cream from the manufacturers like Ponds, Nevia, and Garnier which, under visible light exposure, gets activated by aerial oxygen to generate reactive oxygen species (ROS) harmful to skin.
Keywords: Face cream; Cosmetics; Active microcarbon; rGO; ROS

Augmented antifungal potential of benzothiazol-2-ylcarbamodithioates as hybrid-silver aqua nanoformulations by Anjali Sidhu; Suman R. Ghatelwal; Khushbu Gumber; Anju Bala (617-623).
This study was focused on the preparation of benzothiazol-2-ylcarbamodithioates–silver nanoconjugates (BCDTC–AgNPs) for their in vitro antifungal evaluation against various phytopathogenic fungi viz. Pyricularia grisea, Drechslera oryzae, Fusarium moniliforme and Ustilaginoidea virens. Benzothiazol-2-ylcarbamodithioates (BCDTCs) were used both as capping as well as stabilizing for silver nanoparticles (AgNPs). The prepared nanoconjugates were analysed by UV–visible and TEM studies. The comparative antifungal evaluation of BCDTC–AgNPs with precursor BCDTCs and AgNPs indicated the manifold increase in antifungal potential when applied as nanoconjugates. The promising results were comparable to the standard commercial fungicides Tilt and Bavistin, in most of the cases.
Keywords: Benzothiazol-2-ylcarbamodithioates (BCDTCs); Silver nanoparticles (AgNPs); Capping agent; Stabilizing agent; Antifungal potential; Phytopathogenic fungi

Applicable anode based on Co3O4–SrCO3 heterostructure nanorods-incorporated CNFs with low-onset potential for DUFCs by Zafar Khan Ghouri; Khaled Elsaid; Saeed Al-Meer; Nasser A. M. Barakat (625-631).
Besides the high-current density, lower onset potential of urea electrooxidation is key parameter which influences the direct urea fuel cell performance. In the present article, low-onset potential has been reported for nickel-free (NF) electrocatalyst in urea electrooxidation. The nickel-free electrocatalyst: Co3O4–SrCO3 heterostructure nanorods-incorporated carbon nanofibers (CNFs) were synthesized by electrospinning technique, followed by calcination of electrospun mat composed of strontium acetate, cobalt acetate, and poly(vinyl alcohol) sol–gel in inert environment at 750 °C. Physiochemical characterizations confirmed the formation of Co3O4–SrCO3 heterostructure nanorods-incorporated CNFs. The electrochemical activity of resultant nickel-free electrocatalyst toward the electrooxidation of urea in alkaline medium is evaluated using cyclic voltammetry measurements (CV). Co3O4–SrCO3 heterostructure nanorods-incorporated CNFs reveals high-current density of 21.33 mA/cm2 at low-fuel concentration. Notably, the low-onset potential has been observed, showing a good application prospect in direct urea fuel cells.
Keywords: Electrospinning; Urea; DUFC; Onset potential; Electrocatalyst; Current density

Facile synthesis of microporous SiO2/triangular Ag composite nanostructures for photocatalysis by Sidhharth Sirohi; Anandpreet Singh; Chakit Dagar; Gajender Saini; Balaram Pani; Ratyakshi Nain (633-643).
In this article, we present a novel fabrication of microporous SiO2/triangular Ag nanoparticles for dye (methylene blue) adsorption and plasmon-mediated degradation. Microporous SiO2 nanoparticles with pore size <2 nm were synthesized using cetyltrimethylammonium bromide as a structure-directing agent and functionalized with APTMS ((3-aminopropyl) trimethoxysilane) to introduce amine groups. Amine-functionalized microporous silica was used for adsorption of triangular silver (Ag) nanoparticles. The synthesized microporous SiO2 nanostructures were investigated for adsorption of different dyes including methylene blue, congo red, direct green 26 and curcumin crystalline. Amine-functionalized microporous SiO2/triangular Ag nanostructures were used for plasmon-mediated photocatalysis of methylene blue. The experimental results revealed that the large surface area of microporous silica facilitated adsorption of dye. Triangular Ag nanoparticles, due to their better charge carrier generation and enhanced surface plasmon resonance, further enhanced the photocatalysis performance.
Keywords: Photocatalysis; Microporous SiO2 ; Surface plasmon resonance; Composite nanostructures

Crumpled graphene oxide decorated SnO2 nanocolumns for the electrochemical detection of free chlorine by Thiagarajan Soundappan; Kelsey Haddad; Shalinee Kavadiya; Ramesh Raliya; Pratim Biswas (645-653).
A crumpled graphene oxide–SnO2 nanocolumn (CGO–SnO2) composite electrode was fabricated using aerosol-based techniques. First, SnO2 nanocolumn thin films were fabricated using an aerosol chemical vapor deposition (ACVD) technique. The surface of the nanocolumn was then decorated with CGO by electrospray deposition. The CGO–SnO2 electrode was utilized for the electrochemical detection and determination of the free chlorine concentration in aqueous solutions using linear sweep voltammetry (LSV) and amperometric it curve techniques. The CGO–SnO2 electrodes worked through the direct electrochemical reduction of hypochlorite ions (ClO) on the surface of the electrode, which was used to determine the free chlorine concentration. The electrodes operate over a wide linear range of 0.1–10.08 ppm, with a sensitivity of 2.69 µA µM−1 cm−2. Further, selectivity studies showed that these electrodes easily conquer the electrochemical signals of other common ions in drinking water distribution systems, and only shows the electrochemical reduction signals of free chlorine. Finally, the CGO–SnO2 electrodes were successfully employed for the detection of free chlorine in tap water solutions (St. Louis, MO 63130, USA) with a sensitivity of 5.86 µA µM−1 cm−2. Overall, the sensor fabricated using simple and scalable aerosol-based techniques showed a comparable performance to previous studies on amperometric chlorine sensing using carbon-based electrodes.
Keywords: Graphene oxide; SnO2 ; Chlorine detection; Aerosol chemical vapor deposition

Catalytic activity of Ni complexed aminoclay towards the reduction of Cr(V), p-nitrophenol and fluorescein dye by A. Amala Jeya Ranchani; V. Parthasarathy; A. Anitha Devi; B. Meenarathi; R. Anbarasan (655-666).
A green-colored Ni-complexed aminoclay (AC) was synthesized and its size and crystalline nature were confirmed by HRTEM images and XRD, respectively. The AC–Ni system was used as a catalyst towards the reduction of environmental pollutants like Cr(VI), fluorescein (Fluor) and nitrophenol (NiP) individually and also their mixture. The catalytic reduction of Cr(VI) was elaborately studied under different experimental conditions. The thermodynamic parameters were determined. The AC–Ni system exhibited lower energy of activation (E a) value. The apparent rate constant of individual components and their mixture was determined, analyzed and compared with the literature reports. The pollutants present in the mixture exhibited the lower k app value due to the complex formation.
Keywords: AC–Ni catalyst; Reduction reaction; Apparent rate constant; Energy of activation

Currently, human T cell therapy is of considerable scientific interest. In addition, cell encapsulation has become an attractive approach in biomedical applications. Here, we propose an innovative technique of single-cell encapsulation of human T cells using polyelectrolytes combined with gold nanorods. We have demonstrated encapsulation of human Jurkat T cells with poly(sodium 4-styrenesulfonate) (PSS)-coated gold nanorods (PSS-GNRs). Other forms of encapsulation, using polyelectrolytes without GNRs, were also performed. After Jurkat T cells were encapsulated with poly(allylamine hydrochloride) (PAH) and/or PSS-GNRs or PSS, most cells survived and could proliferate. Jurkat T cells encapsulated with a double layer of PSS-GNR/PAH (PSS-GNR/PAH@Jurkat) showed the highest rate of cell proliferation when compared to 24-h encapsulated cells. With the exception of IL-6, no significant induction of inflammatory cytokines (IL-2, IL-1β, and TNF-α) was observed. Interestingly, when encapsulated cells were co-cultured with THP-1 macrophages, co-cultures exhibited TNF-α production enhancement. However, the co-culture of THP-1 macrophage and PSS-GNR/PAH@Jurkat or PSS/PAH@Jurkat did not enhance TNF-α production. No significant inductions of IL-2, IL-1β, and IL-6 were detected. These data provide promising results, demonstrating the potential use of encapsulated PSS-GNR/PAH@Jurkat to provide a more inert T cell population for immunotherapy application and other biomedical applications.
Keywords: Cell encapsulation; Polyelectrolytes; Gold nanorods; Biological activity; Human T cell therapy

Surface capped copper sulfide nano-aquaformulations were prepared by in situ combination of copper ions with sulfide ions using sonochemical method, followed by microwave irradiations, in the presence of capping agents. Prepared nano-aquaformulations were characterized for particle size, morphology and optical properties. The in vitro antifungal evaluations studies indicated multifold efficacy against Alternaria alternata, Drechslera oryzae and Curvularia lunata in comparison to standard used. The in vivo seed treatment on discoloured paddy seeds showed the optimum results on application @ 7μg/ml for 2 h in case of citrate capped copper sulfide nanoformulation (NCuS3). Significant reduction in seed rot and seedling blight was observed with favourable effect on germination and growth parameters at this concentration.
Keywords: Copper sulfide; Nano-aquaformulations; Poisoned food technique; Phytopathogenic fungi; Mycelium growth

Abrasion properties of self-suspended hairy titanium dioxide nanomaterials by Jiao-xia Zhang; Si Liu; Chao Yan; Xiao-jing Wang; Lei Wang; Ya-ming Yu; Shi-yun Li (691-700).
Considering the excellent solubility of pyrrolidone ring organic compounds, the synthesized N-(trimethoxysilyl) propyl-N-methyl-2-pyrrolidone chlorides was tethered onto titanium dioxide (TiO2) nanoparticles to improve dispersion of TiO2, and then polyethylene oxide (PEO) oligomer through ion exchange embraced the tethered TiO2 to obtain a novel self-suspended hairy TiO2 nanomaterials without any solvent. A variety of techniques were carried out to illustrate the structure and properties of the self-suspended hairy TiO2 nanomaterials. It was found that TiO2 nanoparticles embody monodispersity in the hybrid system though the “false reunion” phenomenon occurring due to nonpermanent weak physical cross-linking. Remarkably, self-suspended hairy TiO2 nanomaterials exhibit lower viscosity, facilitating maneuverable and outstanding antifriction and wear resistance properties, due to the synergistic lubricating effect between spontaneously forming lubricating film and nano-lubrication of TiO2 cores, overcoming the deficiency of both solid and liquid lubricants. This make them promising candidates for the micro-electromechanic/nano-electromechanic systems (MEMS/NEMS).
Keywords: Friction and wear properties; Self-suspended hairy nanomaterials; TiO2 nanoparticles; Liquid-like behavior

Synthesis and characterization of titania nanotubes by anodizing of titanium in fluoride containing electrolytes by Akhlaq Ahmad; Ehsan Ul Haq; Waseem Akhtar; Muhammad Arshad; Zubair Ahmad (701-710).
Titania nanotubular structure was prepared by anodizing titanium metal in the fluoride containing electrolytes and studied for hydrogen reduction using photo electrochemical cell. Potentiodynamic scan was performed before actual anodizing to optimize the anodizing conditions. The morphology of the TiO2 nanotubes was investigated by SEM and the presence of TiO2 nanotubes was confirmed. Raman spectroscopy was done to confirm the different phases present. Hydrogen generation capability was revealed by electrochemical testing in three-electrode system in dark and in visible light at 200 W power using Gamry Potentiostat. The corrosion potential of TiO2 nanotubes produced was found to be more active side in potassium hydroxide solution under visible light than in the dark condition. Cathodic polarization behavior of specimens in the presence of light showed more activity towards hydrogen generation than in dark condition. In comparison, the hydrogen generation capability of specimen anodized in 2H15 electrolyte was higher than specimens anodized in other electrolytes. Electrochemical impedance spectroscopy was used to study the charge transfer resistance of the nanotubes produced. The results showed that TiO2 nanotubular structure is a promising material for photoelectrochemical cell. Low-charge transfer resistance also depicts that it can be efficiently used to harvest solar energy.
Keywords: Titania nanotubes; Anodizing; Potentiodynamic scan; Harvest solar energy; Electrochemical

Glucose-installed, SPIO-loaded PEG-b-PCL micelles as MR contrast agents to target prostate cancer cells by Man Theerasilp; Panya Sunintaboon; Witaya Sungkarat; Norased Nasongkla (711-721).
Polymeric micelles of poly(ethylene glycol)-block-poly(ɛ-caprolactone) bearing glucose analog encapsulated with superparamagnetic iron oxide nanoparticles (Glu-SPIO micelles) were synthesized as an MRI contrast agent to target cancer cells based on high-glucose metabolism. Compared to SPIO micelles (non-targeting SPIO micelles), Glu-SPIO micelles demonstrated higher toxicity to human prostate cancer cell lines (PC-3) at high concentration. Atomic absorption spectroscopy was used to determine the amount of iron in cells. It was found that the iron in cancer cells treated by Glu-SPIO micelles were 27-fold higher than cancer cells treated by SPIO micelles at the iron concentration of 25 ppm and fivefold at the iron concentration of 100 ppm. To implement Glu-SPIO micelles as a MR contrast agent, the 3-T clinical MRI was applied to determine transverse relaxivities (r 2*) and relaxation rate (1/T 2*) values. In vitro MRI showed different MRI signal from cancer cells after cellular uptake of SPIO micelles and Glu-SPIO micelles. Glu-SPIO micelles was highly sensitive with the r 2* in agarose gel at 155 mM−1 s−1. Moreover, the higher 1/T 2* value was found for cancer cells treated with Glu-SPIO micelles. These results supported that glucose ligand increased the cellular uptake of micelles by PC-3 cells with over-expressing glucose transporter on the cell membrane. Thus, glucose can be used as a small molecule ligand for targeting prostate cancer cells overexpressing glucose transporter.
Keywords: Drug delivery system; Polymeric micelles; Superparamagnetic iron oxide; MR contrast agents; Targeting nanoparticles

Exact assay of matrix metalloproteinase 9 (MMP9) has attracted considerable attentions for the clinical diagnosis of disease in early stage. In this report, we covalently engineer a fluorescein isothiocyanate-labeled peptide (Pep-FITC) linker containing the specific cleavage substrate of MMP9 onto the surface of hydrothermally reduced nano-graphene oxide (nrGO) to develop a FRET-based nrGO-Pep-FITC nanoprobe for ultrasensitive detection of MMP9. Upon cleavage of the Pep-FITC at the amide bond between Ser and Leu by MMP9, FITC was separated from nrGO, and fluorescence recovery of FITC was proportional to the MMP9 concentration within 0.01–0.06 nM and 0.06–0.15 nM ranges, respectively, in an aqueous solution, exhibiting 0.83 pM of detection limit. This nanoprobe is stable under borate buffer (pH = 7.4) with bovine serum albumin or 0.1% surfactant Triton 100 or Tween 20, and has good specificity for MMP9 detection, which is meaningful for MMP9-related clinical and bioanalytical applications.
Keywords: Reduced nano-graphene oxide; Nanoprobe; MMP9; Ultrasensitive detection

Barium soda lime phosphosilicate [(58SiO2–(32 − x)BaO–xCao–6Na2O–4P2O5 (where x = 15, 20, 25 and 30 mol%)] samples were synthesised using conventional sol–gel method at 700 °C sintering temperature. Thermal, structural properties were studied using thermo gravimetric analysis and differential thermal analysis, X-ray diffraction, scanning electron microscopy, fourier transform infrared and Raman spectroscopy. Using Raman spectra non-bridging oxygen concentrations were estimated. The hydroxy-carbonated apatite (HCA) layer formation on samples was analysed for 7 days using simulated body fluid (SBF) soaked samples. The growth of HCA layers self-assembled on the sample surface was discussed as a function of NBO/BO ratio. Results indicated that the number of Ca2+ ions released into SBF solution in dissolution process and weight loss of SB-treated samples vary with NBO/BO ratio. The changes in NBO/BO ratios were observed to be proportional to HCA forming ability of barium soda lime phosphosilicate glasses.
Keywords: Sol–gel; SBF solution; NBO/BO; HCA

The article investigates the effects of NiO (p-type) and TiO2 (n-type) nanoparticles (NPs) on the performance of poly(3-hexylthiophene) (P3HT) and (phenyl-C61-butyric acid methylester) (PCBM) based devices with an inverse geometry. Various weight ratios of these nanoparticles were mixed in the polymer solution using 1,2-dichlorobenzene as solvent. An optimal amount of NPs-doped active layer exhibited higher power conversion efficiency (PCE) of 3.85% as compared to the reference cell, which exhibited an efficiency of 3.40% under white light illumination intensity of 100 mW/cm2. Enhanced PCE originates from increased film roughness and light harvesting due to increased absorption range upon mixing an optimal amount of NPs in the organic-based active layer. Further addition of NiO and TiO2 concentration relative to PCBM resulted in significant agglomeration of nanoparticles leading to degraded device parameters.
Keywords: DCB; EQE; Nanoparticles; BHJ; Active layer; Polymer

In the present work, we synthesized cesium superoxide (CsO2) nanoparticles by solution-processed spray pyrolysis technique. The as-synthesized CsO2 nanoparticles were characterized through Raman spectroscopy, X-ray diffraction, scanning electron microscopy and ultraviolet–visible spectroscopy. The CsO2 nanoparticle-based gas sensor is more selective towards the carbon dioxide (CO2) gas. The sensor shows good gas sensing performance for CO2 gas. Gas sensing mechanism is dominated by the adsorption and desorption process. Through this paper, we studied another dimension of gas sensing process by employing superoxide for gas sensing. The sensing mechanism for cesium superoxide is explained by newly designed “bridging oxygen-free mechanism”.
Keywords: Spray pyrolysis; Cesium superoxide; Gas sensing

Controlling conducting channels of single-walled carbon nanotube array with atomic force microscopy by Jean Pierre Nshimiyimana; Jian Zhang; Xiao Hu; Xiannian Chi; Pei Wu; Siyu Liu; Zongzhi Zhang; Weiguo Chu; Lianfeng Sun (759-764).
In this paper, we report a technique of controlling the number of single-walled carbon nanotubes (SWNTs) between two electrodes. The SWNT devices consist of an array of SWNTs between two silver/palladium electrodes, which are fabricated with electron beam lithography and silver. Using the tip-sample interaction in contact mode of atomic force microscopy (AFM), the number of individual SWNTs can be controllably decreased. The current–voltage measurements indicate that the resistance increases when the conducting channels of SWNTs are reduced. This simple and controllable approach could be useful for the assembly of high performance devices with a desired number of channels for future electronic investigations.
Keywords: Single-walled carbon nanotube; Atomic force microscopy; Manipulation; Conducting channels

This experiment was conducted to evaluate the effects of different levels of nanosilicon dioxide (nSiO2) on performance, egg quality, liver histopathology and concentration of calcium (Ca), phosphorus and silicon (Si) in egg, liver and bone in laying quails. The experiment was administered using 60 laying quails at 16–26 weeks of age with five treatments [0 (control), 500, 1000, 2000 and 4000 mg nSiO2 per kg of diet] and four replicates in a completely randomized design. During the experiment, the amount of feed intake was recorded weekly and performance parameters were measured. During the last 3 days of the experiment, all of the eggs in each replicate were collected and egg quality parameters were measured. At the end of 26 weeks of age, the birds were sacrificed and blood samples were collected. Liver samples from each treatment were fixed in 10% buffered formalin for histopathological assessment. The right thigh bone and a portion of liver were inserted in plastic bags and stored at − 20. The results showed that nSiO2 supplementation significantly affected egg weight and egg mass (P < 0.05). Also, dietary nSiO2 supplementation decreased the yolk weight and increased the shell weight (P < 0.05). Moreover, nSiO2 increased bone ash content, Ca and Si concentration in the bone (P < 0.05). The liver enzymes in plasma and the liver tissue histopathology were not significantly affected (P > 0.05) by dietary treatments. In conclusion, the results indicated that dietary supplementation of nSiO2 could improve bone density and performance without any adverse effect on the health of laying quails.
Keywords: Nanosilicon dioxide; Performance; Tissues minerals; Laying quails

Enzyme-free monitoring of glucose utilization in stimulated macrophages using carbon nanotube-decorated electrochemical sensor by Sasya Madhurantakam; Jayanth Babu Karnam; John Bosco Balaguru Rayappan; Uma Maheswari Krishnan (773-780).
Carbon nanotubes (CNTs) have been extensively explored for a diverse range of applications due to their unique electrical and mechanical properties. CNT-incorporated electrochemical sensors have exhibited enhanced sensitivity towards the analyte molecule due to the excellent electron transfer properties of CNTs. In addition, CNTs possess a large surface area-to-volume ratio that favours the adhesion of analyte molecules as well as enhances the electroactive area. Most of the electrochemical sensors have employed CNTs as a nano-interface to promote electron transfer and as an immobilization matrix for enzymes. The present work explores the potential of CNTs to serve as a catalytic interface for the enzymeless quantification of glucose. The figure of merits for the enzymeless sensor was comparable to the performance of several enzyme-based sensors reported in literature. The developed sensor was successfully employed to determine the glucose utilization of unstimulated and stimulated macrophages. The significant difference in the glucose utilization levels in activated macrophages and quiescent cells observed in the present investigation opens up the possibilities of new avenues for effective medical diagnosis of inflammatory disorders.
Keywords: Multi-walled carbon nanotubes; Enzymeless detection; Electrochemical biosensor; Glucose; Macrophages

Bimetallic magnetic PtPd-nanoparticles as efficient catalyst for PAH removal from liquid media by A. F. S. Zanato; V. C. Silva; D. A. Lima; M. J. Jacinto (781-791).
Monometallic Pd- and bimetallic PtPd-nanoparticles supported on a mesoporous magnetic magnetite@silica matrix resembling a core–shell structure (Fe3O4@mSiO2) have been fabricated. The material was characterized by transmission electron microscope (TEM), high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), X-ray photoelectron spectra (XPS), energy dispersive spectroscopy (EDS) and inductively coupled plasma mass spectrometry (ICP-MS). The catalysts were applied in the removal of anthracene from liquid phase via catalytic hydrogenation. It was found that anthracene as a model compound could be completely converted into the partially hydrogenated species by the monometallic and bimetallic solids. However, during the recycling study the bimetallic material (Fe3O4@mSiO2PtPd-) showed an enhanced activity towards anthracene removal compared with the monometallic materials. A single portion of the PtPd-based catalyst can be used up to 11 times in the hydrogenation of anthracene under mild conditions (6 atm of H2, 75 °C, 20 min). Thanks to the presence of a dense magnetic core, the catalysts were capable of responding to an applied external magnetic field and once the reaction was completed, catalyst/product separation was straightforward.
Keywords: Anthracene; Bimetallic catalyst; Catalytic hydrogenation; Magnetic separation; Mesoporous silica

Eco-friendly biosynthesis, anticancer drug loading and cytotoxic effect of capped Ag-nanoparticles against breast cancer by M. Naz; N. Nasiri; M. Ikram; M. Nafees; M. Z. Qureshi; S. Ali; A. Tricoli (793-802).
The work aimed to prepare silver nanoparticles (Ag-NPs) from silver nitrate and various concentrations of the seed extract (Setaria verticillata) by a green synthetic route. The chemical and physical properties of the resulting Ag-NPs were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectrometry and ultraviolet–visible (UV–Vis) spectrophotometry. Anticancer activity of Ag-NPs (5–20 nm) had dose-dependent cytotoxic effect against breast cancer (MCF7-FLV) cells. The in vitro toxicity was studied on adult earthworms (Lumbricina) resulting in statistically significant (P < 0.05) inhibition. The prepared NPs were loaded with hydrophilic anticancer drugs (ACD), doxorubicin (DOX) and daunorubicin (DNR), for developing a novel drug delivery carrier having significant adsorption capacity and efficiency to remove the side effects of the medicines effective for leukemia chemotherapy.
Keywords: Drug loading; Seed extract; Cytotoxicity; Anthelmintic activity; Ag-NPs

Temperature-dependent thermal conductivity and viscosity of synthesized α-alumina nanofluids by Janki Shah; Mukesh Ranjan; Vipul Davariya; Sanjeev K. Gupta; Yogesh Sonvane (803-813).
In the present work, we focused on the thermal conductivity and viscosity of the synthesis as well as characterize metal oxide α-Al2O3 nanoparticles suspended in distilled water:ethylene glycol (60:40) ratio based stable colloidal nanofluid. The band gap of the α-Al2O3 with and without surfactant is 4.42 and 4.59 eV, respectively. The results show that nanoparticle with polyvinyl alcohol surfactant has smaller crystalline size (~23 nm) than without surfactant (~36 nm). The synthesized nanofluids have good stability after 15 days of synthesis which is characterized by zeta potential analyzer. Thermal conductivity and viscosity are measured for 0.1 and 0.5 wt% concentration of alumina for with and without surfactant. The concentration of particles and added surfactant are responsible for stable fluid, thermal conductivity enhancement, and viscosity of nanofluid with respect to temperature. Therefore, the novel combinations of characterized properties of α-Al2O3 nanofluid has proved to be the best thermally stable heat transfer fluid compared to conventional cooling fluids.
Keywords: α-Al2O3 nanoparticles; Nanofluid; Thermal conductivity; Viscosity

Fabricated CeO2 nanopowders as a novel sensing platform for advanced forensic, electrochemical and photocatalytic applications by B. S. Rohini; H. Nagabhushana; G. P. Darshan; R. B. Basavaraj; S. C. Sharma; R. Sudarmani (815-833).
In Forensic investigation, identification of various types of ridge details are essential in order to fix the criminals associated in various crimes. Even though several methods and labeling agents are available to visualize latent finger prints (LFPs) there is still simple, accurate, cost-effective, and non-destructive tool is required. In the present work, CeO2 nanopowders (NPs) are prepared via simple solution combustion route using Tamarindus indica fruit extract as a fuel. The optimized NPs are utilized for visualization of LFPs on various surfaces by powder dusting method. Results revealed that visualized LFPs exhibit Level 3 features such as pores and ridge contours under normal light with high sensitivity and without background hindrance. The photometric characteristics of the prepared samples exhibit blue color emission and highly useful in warm light emitting diodes. The photocatalytic studies were carried out with different Methylene blue (MB) dye concentration and pH values. The obtained results reveal that the CeO2 NPs exhibits an excellent catalytic properties which can act as a good catalytic reagent. The findings demonstrate that the prepared NPs are quite useful as a labeling agent for visualization of LFPs, efficient catalysts for dye degradation as well as solid-state lighting applications.
Keywords: Tamarindus indica ; Latent fingerprints; Solution combustion route; Photoluminescence; Photocatalytic activity

Assembling of carbon nanotubes film responding to significant reduction wear and friction on steel surface by Bin Zhang; Yong Xue; Li Qiang; Kaixong Gao; Qiao Liu; Baoping Yang; Aiming Liang; Junyan Zhang (835-842).
Friction properties of carbon nanotubes have been widely studied and reported, however, the friction properties of carbon nanotubes related on state of itself. It is showing superlubricity under nanoscale, but indicates high shear adhesion as aligned carbon nanotube film. However, friction properties under high load (which is commonly in industry) of carbon nanotube films are seldom reported. In this paper, carbon nanotube films, via mechanical rubbing method, were obtained and its tribology properties were investigated at high load of 5 to 15 N. Though different couple pairs were employed, the friction coefficients of carbon nanotube films are nearly the same. Compared with bare stainless steel, friction coefficients and wear rates under carbon nanotube films lubrication reduced to, at least, 1/5 and 1/(4.3–14.5), respectively. Friction test as well as structure study were carried out to reveal the mechanism of the significant reduction wear and friction on steel surface. One can conclude that sliding and densifying of carbon nanotubes at sliding interface contribute to the sufficient decrease of friction coefficients and wear rates.
Keywords: Carbon nanotubes; Friction; Wear; Films; Lubrication

Green synthesis of silver nanoparticles using Azadirachta indica leaf extract and its antimicrobial study by Pragyan Roy; Bhagyalaxmi Das; Abhipsa Mohanty; Sujata Mohapatra (843-850).
In this study, green synthesis of silver nanoparticles was done using leaf extracts of Azadirachta indica. The flavonoids and terpenoids present in the extract act as both reducing and capping agent. Microbes (Escherichia coli and Gram-positive bacteria) were isolated from borewell water using selective media. The silver nanoparticles showed antimicrobial activities against Gram-positive bacteria and E. coli. However the silver nanoparticles were more effective against E. coli as compared to Gram-positive bacteria. Various techniques were used to characterize synthesized silver nanoparticles such as DLS and UV–visible spectrophotometer. The absorbance peak was in the range of 420–450 nm, that varied depending upon the variation in the concentration of neem extract. This is a very rapid and cost-effective method for generation of silver nanoparticle at room temperature, however, its exact dose in water purification has to be determined.
Keywords: Green synthesis; Silver nanoparticles; Azadiracta indica ; E. coli ; Antimicrobial

In the present work, AgNPs were prepared using a simple bio-reduction method. This is ecologically welcoming and cost-effective method. Yellow colored blooms concentrate of Argemone mexicana and Turnera ulmifolia are used as bio reducing agents in the study. The formation of silver nanoparticles was confirmed by UV–Vis spectrophotometer and characterization of the nanoparticles was done by FTIR, SEM, XRD and EDX. The Antibacterial action of silver nanoparticles was tested against Staphylococus aureus, Pseudomonas aeruginosa, Escherichia coli and Klebsiella aerogenes. The phytochemical analysis of the blooms concentrate has shown the existence of saponins, alkaloids, amino acids, phenols, tannins, terpenoids, flavonoids and cardiac glycosides. In vitro anti-oxidant action of both A. mexicana and T. ulmifolia AgNPs were studied by DPPH assay and reducing power assay.
Keywords: Phytochemical assay; Argemone mexicana ; Turnera ulmifolia ; Blooms concentrate; DPPH assay; Reducing power assay

Drastic improvement in magnetization of CdO nanoparticles by Fe doping by Wael Z. Tawfik; Mohamed Esmat; S. I. El-Dek (863-870).
Hydrothermal route was used in the preparation of Fe-doped CdO nanoparticles with 3, 5, 7 and 10 wt% and their structural and magnetic properties were investigated. Structural characterization using powder X-ray diffraction confirmed the single phase cubic symmetry of these nanoparticles. Particle size decreased monotonically with increasing the dopant ion concentration. The microstructure of the synthesized samples was studied by a high-resolution transmission electron microscopy (HRTEM) which confirmed the nanocrystalline nature of the samples. A vibrating sample magnetometer provided the hysteresis curves of all samples. Pure CdO reveals ferromagnetic behavior while antiferromagnetization is observed for all Fe-doped samples. Large coercivity as well as large area for the sample x = 0.05 is achieved.
Keywords: DMS; Fe-doped CdO; Coercivity; Spin valve

Ceria-based solid solutions doped by Gd and/or Bi were synthesized by co-precipitation method from acid aqueous solution of cerium, gadolinium, and bismuth salts, followed by calcination at the temperature of 500 °C. Characterization of the synthesized samples by many methods was carried out. It is shown that all obtained powders of solid solutions crystallized into a cubic structure of the fluorite type, with an average particle size of 10–17 nm, and for the sample obtained through intermediate acetylacetonate complexes was 5–8 nm. The samples had a mesoporous structure with a pore diameter of 2–5 nm. These systems were tested as the catalysts in CO oxidation in the model gas mixture by the flow method. Gd0.05Bi0.15Ce0.8O2 system obtained through intermediate acetylacetonates has the highest activity, so this sample can be used as a catalyst.
Keywords: Ceria; Solid solution; CO oxidation

We describe the production of size-selected manganese nanoclusters using a magnetron sputtering/aggregation source. Since nanoparticle production is sensitive to a range of overlapping operating parameters (in particular, the sputtering discharge power, the inert gas flow rates, and the aggregation length), we focus on a detailed map of the influence of each parameter on the average nanocluster size. In this way, it is possible to identify the main contribution of each parameter to the physical processes taking place within the source. The discharge power and argon flow supply the metal vapor, and argon also plays a crucial role in the formation of condensation nuclei via three-body collisions. However, the argon flow and the discharge power have a relatively weak effect on the average nanocluster size in the exiting beam. Here the defining role is played by the source residence time, governed by the helium supply (which raises the pressure and density of the gas column inside the source, resulting in more efficient transport of nanoparticles to the exit) and by the aggregation path length.
Keywords: Nanoparticles; Nanoclusters; Vapor aggregation; Mass spectrometry

Enhanced photocatalytic activity of ZnO nanoparticles grown on porous silica microparticles by M. S. Azmina; R. Md Nor; H. A. Rafaie; N. S. A. Razak; S. F. A. Sani; Z. Osman (885-892).
ZnO nanoparticles (NPs) have been synthesized on porous silica microparticles, namely sand microparticles using the sol–gel technique. The ZnO NPs grown on the multifaceted surface of porous silica microparticles were applied as photocatalyst for the degradation of methylene blue (MB) in aqueous solution. The enhanced rate constant observed was due to two reasons. Firstly, the multifaceted surface of the sand substrate provided fixed space for growth space which prevented agglomeration of the ZnO NPs photocatalyst, thus maintaining a large surface area. Secondly, the presence of nanopores on the sand surface provided adsorption sites for MB molecules to be in the vicinity of the photocatalyst. The photocatalytic activity was significantly enhanced where photodegradation efficiency of supported ZnO NPs reached 71.7% compared to 48.2% for unsupported ZnO NPs under UV light irradiation within 150 min. The values of k increased from 4.3 × 10−3 min−1 to 8.6 × 10−3 min−1 for unsupported and supported ZnO NPs, respectively.
Keywords: Photocatalyst; Zinc oxide; Nanoparticles; Photodegradation; Porous silica

Immobilized aptamer on gold electrode senses trace amount of aflatoxin M1 by Amit Kumar Pandey; Yudhishthir Singh Rajput; Rajan Sharma; Dheer Singh (893-903).
An electrochemical aptasensor for detection of trace amounts of aflatoxin M1 was developed. This required immobilization of aptamer on screen printed gold electrode comprising of working electrode, counter electrode and reference electrode and was achieved by sequentially layering dithiodipropionic acid, streptavidin and biotinylated-tetraethylene glycol-aptamer. Immobilization of aptamer was monitored by cyclic voltammetry. Peak current in square wave voltammogram was inversely related to logarithmic concentration of aflatoxin M1. Dynamic range of sensor was 1–105 ppt aflatoxin M1. Sensor can be regenerated by treating electrode with 10% sodium dodecyl sulfate or 40 mM tris-HCl (pH 8.0) containing 10 mM ethylenediaminetetraacetic acid and 0.02% tween-20.
Keywords: Electrochemical aptasensor; Aflatoxin M1; Aptamer; Square wave voltammetry

In recent time, various phytosynthetic methods have been employed for the fabrication of silver nanoparticles; these unique metal nanoparticles are used in several applications which include pharmaceuticals and material engineering. The current research reports a rapid and simple synthetic partway for silver nanoparticles (AgNPs) using root bark aqueous extract of Annona muricata and the evaluation of its antimicrobial efficacy against pathogenic microorganisms. The root bark extract was treated with aqueous silver nitrate solution. Silver ions were reduced to silver atoms which on aggregation gave Silver nanoparticles; the biosynthesized AgNPs were characteristically spherical, discreet and stabilized by phytochemical entities and were characterized using ultraviolet visible spectroscopy, transmission electron microscope (TEM) and photon correlation microscopy. The aqueous plant extract-AgNPs suspension was subjected to Fourier transform infrared spectroscopy. TEM result for the average particle size is 22 ± 2 nm. The polydispersity index and zeta-potential were found to be 0.44 ± 0.02 and − 27.90 ± 0.01 mV, respectively (Zeta-Sizer). The antimicrobial evaluation result showed that the synthesized silver nanoparticles at different concentration were very active against the Gram-positive bacteria (B. subtilis, S. aureous) and Gram-negative bacteria (K. Pneumonia, E. Coli and Pseudomonas aeruginosa), P. aeruginosa being most susceptible to the anti microbial effect of the silver nanoparticles. Stable silver nanoparticles with antimicrobial activity were obtained through biosynthesis.
Keywords: Characterization; Antimicrobial; Silver nanoparticle; Photon correlation microscopy

In the present paper, a green method was applied for the synthesis of SrAl2O4 nanostructures with the aid of microwave irradiation and pomegranate juice. SrAl2O4 nanocrystals were obtained when the raw materials were irradiated with 720–900 W for 6–10 min and then calcinated at 550 °C for 5 h. Using pomegranate juice as a dispersion and stabilizing agent, SrAl2O4 nanoparticles have been made with better properties in view of morphology and particle size. Also, the effect of some parameters affecting synthesis process such as microwave power and reaction time on the morphology and particle size of product was studied and optimized. X-ray diffraction and field emission-scanning electron microscopy were used to study and characterize the manufactured SrAl2O4 nanoparticles.
Keywords: SrAl2O4 ; Microwave; Long lasting phosphors; XRD; FE-SEM

Preparation, characterization and X-ray attenuation property of Gd2O3-based nanocomposites by Sangeetha Jayakumar; T. Saravanan; John Philip (919-931).
In an attempt to develop an alternate to lead-based X-ray shielding material, we describe the X-ray attenuation property of nanocomposites containing Gd2O3 as nanofiller and silicone resin as matrix, prepared by a simple solution-casting technique. Gd2O3 nanoparticles of size 30 and 56 nm are used at concentrations of 25 and 2.5 wt%. The nanoparticles and the nanocomposites are characterized using X-ray diffraction (XRD) studies, small angle X-ray spectroscopy (SAXS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and atomic force microscopy (AFM). The X-ray attenuation property of nanocomposites, studied using an industrial X-ray unit, shows that nanocomposites containing nanoparticles of size 56 nm (G2) exhibit better attenuation than nanocomposites containing nanoparticles of size 30 nm (G1), which is attributed to the greater interfacial interaction between the G2 nanofillers and silicone matrix. In the case of nanocomposites containing G1 nanoparticles, the interfacial interaction between the nanofiller and the matrix is so weak that it results in pulling out of nanofillers, causing voids in the matrix, which act as X-ray transparent region, thereby reducing the overall X-ray attenuation property of G1 nanocomposites. This is further corroborated from the AFM images of the nanocomposites. The weight loss and heat flow curves of pure silicone matrix and the nanocomposites containing Gd2O3 nanoparticles of size 30 and 56 nm show the degradation of silicone resin, due to chain scission, between 403 and 622 °C. The same onset temperature (403 °C) of degradation of matrix with and without nanoparticles shows that the addition of nanofillers to the matrix does not deteriorate the thermal stability of the matrix. This confirms the thermal stability of nanocomposites. Therefore, our study shows that nanocomposites containing G2 nanoparticles are potential candidates for the development of X-ray opaque fabric material.
Keywords: X-ray attenuation; Gd2O3 ; RTV silicone resin; Nanocomposite

Modeling electrical properties for various geometries of antidots on a superconducting film by Sajjad Ali Haider; Syed Rameez Naqvi; Tallha Akram; Muhammad Kamran; Nadia Nawaz Qadri (933-945).
Electrical properties, specifically critical current density, of a superconducting film carry a substantial importance in superconductivity. In this work, we measure and study the current–voltage curves for a superconducting Nb film with various geometries of antidots to tune the critical current. We carry out the measurements on a commercially available physical property measurement system to obtain these so-called transport measurements. We show that each of the used geometries exhibits a vastly different critical current, due to which repeatedly performing the measurements independently for each geometry becomes indispensable. To circumvent this monotonous measurement procedure, we also propose a framework based on artificial neural networks to predict the curves for different geometries using a small subset of measurements, and facilitate extrapolation of these curves over a wide range of parameters including temperature and magnetic field. The predicted curves are then cross-checked using the physical measurements; our results suggest a negligible mean-squared error—in the order of $$10^{-9}$$ 10 - 9 .
Keywords: Critical fields; Transport properties; Critical currents; Vortex pinning; Artificial neural networks

Effects of silica-based nanostructures with raspberry-like morphology and surfactant on the interfacial behavior of light, medium, and heavy crude oils at oil-aqueous interfaces by Lingyun Bai; Chunyan Li; Caroline Korte; Britta M. J. Huibers; Ashley R. Pales; Wei-zhen Liang; David Ladner; Hugh Daigle; Christophe J. G. Darnault (947-972).
Any efficient exploitation of new petroleum reservoirs necessitates developing methods to mobilize the crude oils from such reservoirs. Here silicon dioxide nanoparticles (SiO2 NPs) were used to improve the efficiency of the chemical-enhanced oil recovery process that uses surfactant flooding. Specifically, SiO2 NPs (i.e., 0, 0.001, 0.005, 0.01, 0.05, and 0.1 wt%) and Tween®20, a nonionic surfactant, at 0, 0.5, and 2 critical micelle concentration (CMC) were varied to determine their effect on the stability of nanofluids and the interfacial tension (IFT) at the oil–aqueous interface for 5 wt% brine-surfactant-SiO2 nanofluid-oil systems for West Texas Intermediate light crude oil, Prudhoe Bay medium crude oil, and Lloydminster heavy crude oil. Our study demonstrates that SiO2 NPs may either decrease, increase the IFT of the brine-surfactant-oil systems, or exhibit no effects at all. For the brine-surfactant-oil systems, the constituents of the oil and aqueous substances affected the IFT behavior, with the nanoparticles causing a contrast in IFT trends according to the type of crude oil. For the light oil system (0.5 and 2 CMC Tween®20), the IFT increased as a function of SiO2 NP concentration, while a threshold concentration of SiO2 NPs was observed for the medium (0.5 and 2 CMC Tween®20) and heavy (2 CMC Tween®20) oil systems in terms of IFT trends. Concentrations below the SiO2 NP threshold concentration resulted in a decrease in IFT, and concentrations above this threshold resulted in an increase in IFT. The IFT decreased until the NP concentration reached a threshold concentration where synergetic effects between nonionic surfactants and SiO2 NPs are the opposite and result in antagonistic effects. Adsorption of both SiO2 NPs and surfactants at an interface caused a synergistic effect and an increased reduction in IFT. The effectiveness of the brine-surfactant-SiO2 nanofluids in decreasing the IFT between the oil-aqueous phase for the three tested crude oils were ranked as follows: (1) Prudhoe Bay > (2) Lloydminster > and (3) West Texas Intermediate. The level of asphaltenes and resins in these crude oil samples reflected these rankings. A decrease in the IFT also indicated the potential of the SiO2 NPs to decrease capillary pressure and induce the movement and recovery of oil in original water-wet reservoirs. Conversely, an increase in IFT indicated the potential of SiO2 NPs to increase capillary pressure and oil recovery in reservoirs subject to wettability reversal under water-wet conditions. Raspberry-like morphology particles were discovered in 5 wt% brine-surfactant-SiO2 nanofluid-oil systems. The development of raspberry-like particles material with high surface area, high salt stability, and high capability of interfaces alteration and therefore wettability changes offers a wide range of applications in the fields of applied nanoscience, environmental engineering, and petroleum engineering.
Keywords: Nanomaterials; Multiphase fluids; Interfacial processes; Adsorption; Crude oils; Tween®20; Enhanced oil recovery (EOR); Raspberry-like morphology particles

Herbal liposome for the topical delivery of ketoconazole for the effective treatment of seborrheic dermatitis by Vivek Dave; Swati Sharma; Renu Bala Yadav; Udita Agarwal (973-987).
The aim of the present study was to develop liposomal gel containing ketoconazole and neem extract for the treatment of seborrheic dermatitis in an effectual means. Azoles derivatives that are commonly used to prevent superficial fungal infections include triazole category like itraconazole. These drugs are available in the form of oral dosage that required a long period of time for treatment. Ketoconazole is available in the form of gel but is not used with any herbal extract. Neem (Azadirachta indica) leaves show a good anti-bacterial and anti-fungal activity and have great potential as a bioactive compound. The thin film hydration method was used to design an herbal liposomal preparation. The formulation was further subjected to their characterization as particle size, zeta potential, entrapment efficiency, % cumulative drug release, and anti-fungal activity and it was also characterized by the mean of their physicochemical properties such as FTIR, SEM, DSC, TGA, and AFM. The results show that the formulation of liposomes with neem extract F12 were found to be optimum on the basis of entrapment efficiency in the range 88.9 ± 0.7%, with a desired mean particle size distribution of 141.6 nm and zeta potential − 45 mV. The anti-fungal activity of liposomal formulation F12 was carried out against Aspergillus niger and Candida tropicalis by measuring the inhibition zone 8.9 and 10.2 mm, respectively. Stability of optimized formulation was best seen at refrigerated condition. Overall, these results indicated that developed liposomal gel of ketoconazole with neem extract could have great potential for seborrheic dermatitis and showed synergetic effect for the treatment.
Keywords: Ketoconazole; Neem extract; Seborrheic dermatitis; Liposomal gel; Anti-fungal activity