International Journal Of Bio-Inorganic Hybrid Nanomaterials
Volume:4 Issue: 3, Autumn 2015

The present study deals with the synthesis andfunctionalization of mesoporous silica nanoparticles as drug delivery platforms. SBA-15 nanorods with high surface area (1010 m2g-1) were functionalized by post grafting method using 3-mercaptopropyl trimethoxysilane (MPTS). The parent and thiol-functionalized SBA-15 nanorods were used as nanocarriers for an anticancer drug (gemcitabine). The characterization of all samples were done by small angle X-ray scattering (SAXS), N2 adsorption/desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), FTIR and UV spectroscopies. The adsorption and release properties of all samples were investigated. It was found that the surface functionalization increases the interaction between the carrier and gemcitabine and results in the loading enhancement of the drug. The obtained results reveal that the surface functionalization leads towards significant decrease of the drug release rate. These findings demonstrate that the functionalized mesoporous system is appropriate drug delivery platform due to their loading content and the possibility to modify drug release.

Sphere-like shaped cobalt oxide nanoparticles (Co3O4) were synthesized by a simple wet chemical method using cobalt chloride as precursor and cetyl trimethylammonium bromide (CTAB) as surfactant. Their structural and surface morphologial properties were characterized by high resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). XRD measurement exhibited the structure of Co3O4 nanocrystals for annealed samples. The TEM results showed the sphere-like shaped cobalt oxide nanoparticles with good uniformity in the presence of CTAB surfactant. The SEM images revealed that the particles changed to spherical shape and the size of cobalt oxide nanoparicles increased in the range of 25-45 nm with increasing annealing temperature.

Antibacterial activity of Fe3O4 nanoparticles was investigated in three microorganisms including P. aeruginosa, E. Coli and Staphylococcus aureus. Fe3O4 nanoparticles were synthesized by chemical precipitation method (20 nm). The Fe3O4 nanoparticles antibacterial effect against Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus were studied by the culture method. First of all, each bacterium was grown in nutrient broth culture environment aerobically for 24 h at 37°C. After that, about 1 mL of each bacterium was placed onto a plate which was previously prepared by Mueller Hinton Agar culture environment. Their characteristics and physical properties were evaluated by X-ray diffraction (XRD), Alternating Gradiant Force Magnetometer (AGFM) and Transmission Electron Microscope (TEM). Antibacterial effects of Fe3O4 nanoparticles (1.56 to 25 mg/ mL concentrations) against three pathogenic bacteria including Pseudomonas aeroginosa, Escherichia coli and Staphylococcus aureus were studied using well diffusion bacteriological test. The inhibition zone diameter was directly and strongly correlated to the nanoparticles concentration and Pseudomonas aeroginosa was the most sensitive bacterium to the Fe3O4 nanoparticles. The maximum diameter of inhibition zone was occurred for P. aeroginosa bacteria for both Fe3O4 samples. The most sensitive bacterium among three pathogenic bacteria tested was P. aeroginosa.

A novel modified Ni-ZSM-5 nanozeolite was fabricated via an organic template-free hydrothermal route. The average particle size of Ni-ZSM-5 nanozeolite was calculated to be 85 nm by scanning electronic microscopy. Then, Carbon paste electrode (CPE) was modified by Ni-ZSM-5 nanozeolite and Ni2 ions were then incorporated to the nanozeolite matrix. Electrochemical behavior of this electrode was investigated by cyclic voltammetry that exhibits stable redox behavior of Ni(III)/ Ni(II) couple in alkaline medium. It has been shown that Ni-ZSM-5 nanozeolite at the CPE surface can improve catalytic efficiency of the dispersed nickel ions toward formaldehyde (HCHO) electrocatalytic oxidation. The values of electron transfer coefficient, charge-transfer rate constant and the electrode surface coverage were obtained to be 0.49, 0.045 s−1 and 4.11×10−8 mol cm−2, respectively. Also, the catalytic rate constant for HCHO and redox sites of electrode and diffusion coefficient were found to be 9.064×103 cm3 mol−1 s−1 and 8.575 ×10−6 cm2 s−1, respectively.

Magnetic nanoparticles are the good choice for using in MRI as the contrast agent. Iron oxide particles such as magnetite (Fe3O4) or its oxidized form maghemite (γ-Fe2O3) are the most commonly employed in biomedical applications. In this study, we synthesized and optimized the preparation of chitosan manganese-ferrite nanoparticles (CMn-Fe nps) and evaluated its ability for the mice macrophage cells imaging with MRI. The core and hydrodynamic size of the nanoparticles was 54±27 nm and 149±48 nm respectively. The magnetization reached a saturation magnetization value of 95 emu/g. The MRI images showed that the liver and some other organs were accumulated the CMn-Fe nps and produced a negative contrast in images. CMn-Fe nps demonstrated that it is a good candidate for using as a contrast agent material in macrophage cells imaging with MRI.

In this study, catalyst of rutile titanium dioxide nanoparticles (rTiO2-NP) has been investigated for the removal and reduction of unburned hydrocarbons as benzopyran. To evaluate and calculate the thermodynamic properties of this aim, pollutants are closed to the nanoparticles and converted them into other products and the carbon dioxide molecules are simulated in the 12th steps. The geometrical structure of all stages is optimized by Density Functional Theory (DFT) method based on B3LYP/631G. The structure of rutile titanium dioxide nanoparticles, there are several different locations on it as the cross bridge Ti-O and Ti-Ti, the thermodynamic properties of these conversions and locations are calculated by a semi empirical method (ZINDO/S). The results shown these interactions are exothermic and spontaneous. The total energy (kcal/mol) for conversion benzopyran on Ti-O bond is lower than Ti-Ti bond. Therefore the probability of interaction with Ti-O is more. This phenomenon dramatically increases the electrical conductivity of the nano-particles, suggesting that the rTiO2-NP may be potential sensor for benzopyran gaseous molecule detection.

A simple, highly sensitive, accurate and selective method for determination of trace amounts of Cu2 in water samples was reported. In this paper, Isopropyl 2-[(isopropoxy carbothioyl)disulfanyl] ethanethioate (IIDE) in order to prepare an effective sorbent for the preconcentration and determination of Cu. The sorption capacity of Isopropyl 2-[(isopropoxy carbothioyl)disulfanyl]ethanethioate (IIDE)modified Octadecane-functionalized nano graphene (OD-G) (IIDE MS) was 82.34 mg.g-1 and the optimum pH for the quantitative recovery of Cu was found as 5.3. The optimum flow rate, sorbent amount and sample volume were 8 mL.min-1, 300 mg and 50 mL, respectively. 10 mL of 0.1 mol.L-1 HCl was the most suitable eluent. The recommended method is simple and reliable for the determination of Cu without any notable matrix effect and successfully applied to environmental water samples. The limit of detection of the proposed method is 7.5 ng per mL. The method was applied to the extraction and recovery of Cu(II) in different water samples. In the present study, we report the application of preconcentration techniques still continues increasingly for trace metal determinations by flame atomic absorption spectrometry (FAAS) for quantification of Cu in Formalin-fixed paraffin-embedded (FFPE) tissues from Liver loggerhead turtles. This method exhibits the superiority in compared to the other adsorption reagents because of the fact that there is no necessity of any complexing reagent and optimum pH of solution presents in acidic media. In this method is relative standard deviation (R.S.D.) of 2.7%.

One-pot, four-component procedure for the synthesis of a small library of new chiral spiro- oxindolopyrrolidines with high regio-, diastereo- (>99:1 dr), and enantioselectivity (up to 80% ee) is described. In this process, the regio- and stereochemical 1,3-dipolar cycloaddition of azomethine ylides, which were generated insitu by the reaction of isatin derivatives and sarcosin,with optically active chiral menthyl cinnamate studied on the basis of the assignment of the absolute configuration of the cycloadducts, and on theoretical calculations. In comparison with active cinnamoyl oxazolidinone, when the reactions were performed with active chiral menthyl cinnamate as dipolarophile, a remarkable unexpected inversion in the regioselectively was observed. The regioselectivity of the reactions was investigated using global and local reactivity indices at the B3LYP/6-311G(d,p) level of theory. The effects of the electronic and steric factors on the regioselectivity of the reactions were discussed. The electronic structures of critical points were studied by the natural bond orbital (NBO) method.