Nanobiosensor designing with molecular framework polymer method compared with agent-linked nanosilica biosensor for Staphylococcus aureus exotoxin detection

Considering the ever increasing population and industrialization leading to developmental trend of humankind's life, we are hardly able to detect the toxins produced in food products using traditional techniques. In this technique, the production of molecular framework and polymer is done using meta acrylic acid monomers, which are formed via covalence connection between meta acrylic acid monomers (MAA) of white polymer. Here also hydrogenised connection between exotoxin amino acid and meta acrylic acid is made that would function as the selective absorption for that. Then in the second stage, based on the bacterial antibody connection to nanoparticle, a sensor was used. In this part of the research, as the basis for absorption for the recognition of bacterial toxin, medium sized silica nanoparticles of 10 nanometer in the form of solid powder were utilized with Notrino brand. Then the suspension produced from agent-linked nanosilica which was connected to bacterial antibody was positioned near the samples of distilled water, that were contaminated with Staphylococcus aureus bacterial toxin with the density of 10^-3, so that in case any toxin exists in the sample, a connection between toxin antigen and antibody would be formed. Finally, the light absorption related to the connection of antigen to the particle attached antibody was measured using spectrophotometers. The results indicate that the molecular framework polymer sensor is capable of detecting up to the density of 10^-3, but not lower than that, whereas using the second sensor, up to 10^-4 of density is detectable. Additionally, the sensitivity of the sensors were examined after 60 days and the first sensor by the day of 28 and the second sensor by the 56 day had confirmatory results and started to decrease after those time periods

Determination of Sodium Benzoate and Potassium Sorbate in “Doogh” Samples in Post Market Surveillance in Iran 2012

<p>Sodium benzoate and potassium sorbate are two major chemical preservatives which are used in Doogh (Iranian traditional dairy drink). In this study, a total of 27 commercial brands of highly consumed of Doogh samples were analyzed. The means and standard deviation for concentration of these preservatives based on HPLC results for analysis of benzoate and sorbate were 195·9 (SD 1·8) and 328·8 (SD 2·1) mg.Kg^-1 respectively. The minimum and maximum of benzoate content in various brands were 18.3 and 2345.1 mg.Kg^-1 and for sorbate were not detected and 4961.3 mg.Kg^-1 respectively. The study revealed that there was not significant difference in preservative concentration in the samples that belonged to various dates. However, a few samples had a high preservative concentration, which could be a risk factor for human health, especially when their intake was being occurred by various foodstuffs simultaneously.</p

Synthesis of modified ZnO nanorods and investigation of its application for removal of phthalate from landfill leachate: A case study in Aradkouh landfill site

In this study, zinc oxide nanorods, co-doped with iron and silver, were synthesized in a co-precipitation method. Its properties were determined using X-ray diffraction (XRD), Transmission electron microscopy (TEM), Field Emission Scanning Electron Microscopy (FE-SEM), Brunauer–Emmett–Teller (BET), Dynamic light scattering (DLS) and X-ray photoelectron spectroscopy (XPS) analysis. The results of FE-SEM and TEM showed that zinc oxide nanoparticles synthesized and co-doped with iron and silver were formed as separate nanorods. Also, the average values of DBP and DEHP amount of phthalates in the leachate from the landfill site of Aradkouh were obtained 52.5 and 94.69 mg/L, respectively. The highest removal efficiency in real samples for phthalates was found to be 52%. The highest removal efficiency of TOC were was 61%. The synthesized nanostructure could have proper efficiency in removal of phthalates from water sources under the visible light of LED lamp