International Journal Of Bio-Inorganic Hybrid Nanomaterials
Volume:2 Issue: 3, Autumn 2013

The photocatalytic coatings were prepared via incorporating the modified titania nanoparticles into epoxy-based inorganic-organic hybrid coatings. Titania nanoparticles were first synthesized from tetra-n-butyl titanate using sol-gel methods by two different calcination treatments, i.e., in mild condition (80°C) and 500°C. The formed anatase nanoparticles were further modified as Titania-Silica (TS) core/shell structure. Characterization of the samples was carried by X ray diffraction (XRD) analysis, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), Energy-Dispersive X ray (EDX) spectroscopy and UV-Vis spectroscopy. The decomposition of methylene blue (MB) exhibited high photocatalytic activity for the titania nanoparticles embedded with silica phase in core/shell structure. In a comparative study using a commercial P25 titania from Evonik, the synthesized titania samples showed lower size nanoparticles and more uniform distribution of nanoparticles into hybrid binder. However, the degree of anatase crystalline was lower which results to lower photocatalytic activity.

CoFe2O4 have been synthesized via a surfactant assisted gel microwave route with a molar ratio of Fe/Co= 2 and oleic acid (OA) was used as a surfactant. Fourier Transform Infrared spectroscopy (FTIR), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) were used to consider the structural and morphological properties of CoFe2O4 nano-particles. Results demonstrated that oleic acid is an effective surfactant for producing high crystalline powders. The average particle size and the percentage of crystallinity were calculated 34.7 nm and 90, respectively.

There are various methods for the analysis of Potassium Sorbate and Sodium Benzoate in food products, ut a rapid and reliable method for identification of these preservatives in Doogh (an Iranian traditional dairy drink) is a procedure, in which high performance liquid chromatography (HPLC) utilized and followed by UV diode array detection of the two preservatives. The aim of this case study was determination of Potassium Sorbate and Sodium Benzoate in Doogh, Samples consumed in the city of Tehran, Iran by HPLC in compare of Spectrophotometry method. In this study, 27 samples were analyzed. The HPLC determination of the preservatives was performed reversed-phase; C18 column and UV detected at 225 nm for sodium benzoate and 255 nm for potassium sorbate. In Spectrophotometry method, Sodium benzoate and Potassium sorbate were detected in 228 nm and 250 nm, respectively. The results of spectrophotometry in low concentrations, showed high values in comparison to what had been mention by HPLC. In high concentration, spectrophotometry showed the low value in comparison to HPLC. In conclusion, spectrophotometry could not detect and determine the Potassium sorbate and Sodium benzoate in a sample at the same time with reliable and exact results.

In this work, we report on the synthesis of superparamagnetic iron oxide nanoparticles at room temperature using microemulsion template phase consisting of cyclohexane, water, CTAB as cationic surfactant and butanol as a cosurfactant. Surface modification have been carried out by using poly(ethyleneglycol) (PEG). The structure,morphology, and magnetic properties of the products were characterized by X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and vibrating sample magnetometer (VSM) at room temperature. The results revealed formation of iron oxide nanoparticles, with an average size of 8.8-12 nm, a superparamagnetism behavior with fast response to applied magnetic fields and zero remanence and coercivity.

FePt nanoparticles with thermally stable room-temperature ferromagnetism are investigated. The monodisperse nanoparticles are prepared by chemical synthesis and a salt-matrix annealing technique. Structural and magnetic characterizations confirm the phase transition from the disordered face-centered cubic structure. In this paper, 3 nm FePt nanoparticles are first synthesized by superhydride reduction of Fe and Pt. Transmission Electron Microscopy (TEM) images show that the hard magnetic FePt are agglomerated after annealing at 675°C. Scanning Electron Microscopy (SEM) images indicate that the size of FePt nanoparticles increase by increasing of the annealing temperature.

In the current study, whey protein- pullulan- clay nanocomposite films are prepared by casting method. The effect of nanoclay at three concentrations (1%, 3% and 5%) on physical properties such as moisture content, solubility in water, water vapor permeability and transparency of whey protein- pullulan composite films investigated. The results show that the effect of nanoparticles on composite depends on kind of nanoparticle and level of incorporation. Nanoclay particles changed solubility, water absorption and moisture content of the films but did not influence on transparency.

1,3-dipolar cycloaddition reaction of 1 mol or 2 mol of dibenzalaceton with 1 mol of non stabilized azomethinylides generated in situ by decarboxylative condensation of isatin and proline or sarcosine give the novel new spiro-oxindolo(pyrrolizidines/ pyrrolidines) instead of bis spirooxindolo(pyrrolizidines/ pyrrolidines).

The surface parameter of nanoparticles such as hydrophobicity and a hydrophilicity on protein structure and function is very important. In this study, conformational changes of glucose oxidase (GOx) in the mercaptopurine: GNPs and 11-mercaptoundecanoic acid: GNPs as a hydrophobic and a hydrophilic GNPs surface was investigated by various spectroscopic techniques, including: UV-Vis absorption, fluorescence and circular dichroism (CD) spectroscopies. Moreover, the fluorescence quenching constant and binding parameters after the formation of the GOx: GNPs conjugates follows by Stern-Volmer (S-V) plots. Size of GNPs was determined by Zeta Sizer, which their size is 80 nm. CD and florescence spectroscopy show that the conformational changes in both the secondary and the tertiary structure levels of GOx in conjugate with hydrophobic and hydrophilic-GNPs was occured. Also, Stern-Volmer plots for the binding of hydrophilic-GNPs and hydrophobic-GNPs with GOx was plotted. Stern-Volmer quenching constant, binding constant and the number of binding sites of GOx: GNPs conjugates was determined.