Radioiodination of zearalenone and determination of Lactobacillus plantarum effect of on zearalenone organ distribution: In silico study and preclinical evaluation.

Purpose: Zearalenone (ZEN) which is one of the known fusarium species mycotoxin, produced primarily on many cereal crops. Consequently, the current study aims to estimate the possibility of labeling zearalenone and the pattern of accumulation of the produced labeled zearalenone [125I]-ZEN in different mice tissues, and the possible protective effect of Lactobacillus plantarum to reduce organ accumulation of Zearalenone. Materials and methods: the experiment was conducted on two groups of mice were used; the two groups received [125I] Zearalenone administered by tail vein injection, the first group receive nothing else while the second group received also L. plantarum (as a control agent) orally. The mice were kept under observation for 120 min to monitor zearalenone distribution. Results: by monitoring the zearalenone distribution the maximum concentration was found to be mainly primarily in the intestine (45.8 %) followed by the liver (27.15 %) while in the ovary (the most susceptible organ was (3.22 %) after120 min, in the first group of mice. The same pattern was observed in the second group with concentrations of (46.1 %), (30.19 %) and (0.09 %) in the intestine, liver respectively. Conclusion: These results indicated the lactic acid bacteria played a role in decreasing labeled zearalenone in the ovaries which is the target organ. [125I]-labeled ZEN is a promising novel tracer for organ imaging and that a significant role that L. plantarum could play in decreasing the zearalenone bioavailability of in mice organs.

Proton exchange membrane based on graphene oxide/polysulfone hybrid nano-composite for simultaneous generation of electricity and wastewater treatment.

Microbial fuel cell (MFC) is a combined technology for simultaneous generation of electricity and wastewater treatment. In MFC, the proton exchange membrane (PEM) is an essential component affecting electricity generation. In the current study, two proton exchange membranes, namely sulfonated polyethersulfone (SPES) and graphene oxide/sulfonated -polyethersulfone hybrid nanocomposite (GO-SPES), were prepared and characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The collected information confirmed the successful preparation of the membranes. Moreover, contact angle measurements, ion exchange capacity and degree of sulfonation of the prepared membranes were determined. The results showed that the introduction of GO nanoparticles into SPES membrane improved its proton exchange capability and resulted in better performance. The power density and the current generated from SPES membrane were 60 mW/m2 and 425 mA/m2, respectively. For GO-SPES, the obtained power density was 101.2 mW/m2 and the current was 613 mA/m2. Both membranes showed comparable chemical oxygen demand (COD) removal efficiency of about 80%; suggesting that the prepared membranes are working efficiently in wastewater treatment as PEMs in MFCs. As a final point, the performance of GO-SPES membrane was compared to the performance of the well-known Nafion® 117 membrane and the results were promising. To conclude, the GO-SPES membrane is an outstanding membrane for use as PEM in MFCs for simultaneous generation of electricity and wastewater treatment.

Radioiodination and bioevaluation of rolipram as a tracer for brain imaging: In silico study, molecular modeling and gamma scintigraphy.

Brain imaging is considered one of the most fruitful applications of radioisotope scanning. Rolipram, a selective phospodiesterase-4 inhibitor, has been labeled using [125 I] with chloramine-T (Ch-T) as an oxidizing agent. Factors, such as the amount of substrate, pH, the amount of oxidizing agent, temperature, and the reaction time, have been systematically studied to optimize the iodination process. In addition, bio-distribution studies have indicated that the brain uptake of [125 I]iodorolipram is 7.6 ± 0.33 injected dose/g organ at 10 minutes post-injection, which cleared from the brain with time until it reaches 1.30 ± 0.17% at 1 hour post-injection. Therefore, iodorolipram could be considered as a potential, new selective radiotracer for brain imaging.

Evaluation of the pollution load discharged at an upstream industry--Egypt--and methods for its reduction.

Oil exploration in Egypt is a major contributor to the national Gross Domestic Product (GDP). With 50-65% of the oil resources located in the Gulf of Suez (GoS) region, the impact of such activity upon the region's water environment and its quality cannot be overlooked because of the volume of effluent generated. The objective of this study (September 2000-September 2001) was to assess the impact of a 650,000 barrels/day (bl/d) (100,000 m3/d) effluent arising from a major oil exploration site located south of GoS upon the local water environment. Another objective was to identify the pollutant contents amenable for reduction relative to the new Egyptian regulations. This was achieved by the characterization of the main contributing streams and the identification of the final effluent parameter constraints relative to the type of injection waters used. Subsequent investigations for the reduction of these contents were conducted on site and the results obtained are reviewed herewith.

Sorption characteristics and chromatographic separation of gold (I and III) from silver and base metal ions using polyurethane foams.

The influence of different parameters on the sorption profiles of trace and ultra traces of gold (I) species from the aqueous cyanide media onto the solid sorbents ion exchange polyurethane foams (IEPUFs) and commercial unloaded polyurethane foams (PUFs) based polyether type has been investigated. The retention of gold (I) species onto the investigated solid sorbents followed a first-order rate equation with an overall rate constant k in the range 2.2-2.8+/-0.2 s(-1). The sorption data of gold (I) followed Freundlich and Langmuir isotherm models. Thus, the a dual-mode of sorption mechanism involving absorption related to "weak base anion exchanger" and an added component for "surface adsorption" seems the most likely proposed dual mechanism for retention profile of gold (I) by the IEPUFs and PUFs solid sorbents. The capacity of the IEPUFs and PUFs towards gold (I) sorption calculated from the sorption isotherms was found to be 11.21+/-1.8 and 5.29+/-0.9 mg g(-1), respectively. The chromatographic separation of the spiked inorganic gold (I) from de ionized water at concentrations 5-15 microg mL(-1) onto the developed IEPUFs and PUFs packed columns at 10 mL min(-1) flow rate was successfully achieved. The retained gold (I) species were then recovered quantitatively from the IEPUFs (98.4+/-2.4%, n=5) and PUFs (95.4+/-3.4%, n=5) packed columns using perchloric acid (60 mL, 1.0 mol L(-1)) as a proper eluting agent. Thiourea (1.0 mol L(-1))-H2SO4 (0.1 mol L(-1)) system was also used as eluting agent for the recovery of gold (I) from IEPUFS (95.4+/-5.4%, n=3) and also PUFs (93.4+/-4.4%, n=3) packed columns. The performance of the IEPUFs and PUFs packed columns in terms of the height equivalent to the theoretical plates (HETP), number of plates (N), and critical and breakthrough capacities towards gold (I) species were evaluated. The developed IEPUFs packed column was applied successfully for complete retention and recovery (98.5+/-2.7) of gold (III) species spiked onto tap- and industrial wastewater samples at <10 microg Au mL(-1) after reduction to gold (I). The IEPUFs packed column was applied satisfactorily for complete retention and recovery (98.5+/-2.7) of total inorganic gold (I) and/or gold (III) species spiked to tap- and industrial wastewater samples at <10 microg mL(-1) gold. Chromatographic separation of gold (I) from silver (I) and base metal ions (Fe, Ni, Cu and Zn) using IEPUFS packed columns was satisfactorily achieved. The proposed method was applied successfully for the pre-concentration and separation from anodic slime and subsequent FAAS determination of analyte with satisfactory results (recoveries >95%, relative standard deviations <4.0%).

Chemical enrichment and separation of uranyl ions in aqueous media using novel polyurethane foam chemically grafted with different basic dyestuff sorbents.

The new type of the grafted polyurethane foam sorbents were prepared by coupling polyether polyol, toluene diisocyanate and basic dyestuff (Methylene blue, Rhodamine B and Brilliant green). The Me.B-PUF, Rh.B-PUF and Br.G-PUF were characterized using UV/vis, IR and TGA. The adsorption properties and chromatographic behaviour of these new adsorbents for preconcentration and separation of uranium(VI) ions at low concentrations from aqueous thiocyanate media were investigated by a batch process. The maximum sorption of U(VI) was in the pH ranges 1-4. The kinetics of sorption of the U(VI) by the Grafted-PUF were found to be fast with half life of sorption (t(1/2)) in 2.43min. The average sorption capacity of different sorbents 0.124meqg(-1) for uranyl ions, enrichment factors approximately 40 and the recovery 98-100% were achieved (R.S.D. approximately 0.73%). The basic dyestuff Grafted-PUF could be used many times without decreasing their capacities significantly. The value of the Gibbs free energy (DeltaG) for the sorbents is -7.3kJmol(-1), which reflects the spontaneous nature of sorption process. The sorption mechanism of the metal ion onto Grafted-PUF was also discussed.

The sorption behaviour and separation of some metal thiocyanate complexes on polyether-based polyurethane foam.

The preliminary screening tests on the preconcentration of lanthanum(III), aluminium(III), molybdenum(VI), gallium(III) and tungsten(VI) thiocyanate complexes in aqueous media by unloaded foam indicated a reasonable percentage of metal ions were retained on the foam. The influence of various parameters affecting the retention of these complex species from the aqueous media by the foam were critically studied and the possible mechanisms of the sorption of the compounds were suggested. However, owing to the complex chemical nature of the polyether-polyurethane foam, several mechanisms may be involved simultaneously. Attempts for the quantitative retention and recovery of the tested complexes by the foam columns were also made and satisfactory results were obtained. The height equivalent to theoretical plates (HETP) of the foam columns were calculated from the chromatograms and break through capacity curve and were found in the range 1.8-2.3 mm at flow rates up to 15 cm(3)/min. The proposed foam column method has been successfully used for the separation of a series of complex mixtures of the tested metal thiocyanate complexes in aqueous media. The membrane properties of the foam sorbents offer unique advantages over conventional bulk type granular sorbents in rapid, versatile effective separations and preconcentrations of different complexes from fluid samples.

Iodometric microgram determination of chromium(III) and (VI) by use of chemical amplification reactions.

A simple, rapid and sensitive method is described for the iodometric determination of microgram amounts of chromium(III), based on the oxidation of chromium(III) with periodate at pH 3.2, removal of the unreacted periodate by masking with molybdate and subsequent iodometric determination of the liberated iodate. Chromium(VI) can be determined by this method after prior reduction to chromium(III) with sodium sulphite. The method can also be used for the analysis of organochromium compounds.

Removal of organic pollutants from aqueous solution. V. Comparative study of the extraction, recovery and chromatographic separation of some organic insecticides using unloaded polyurethane foam columns.

The concentration of dissolved insecticides in aqueous media was determined by chromatographic separation on polyurethane foam columns. The results of preliminary screening tests on the removal of insecticides by the unloaded polyurethane foam indicated that a reasonable percentage of the insecticides was retained on the foam. Therefore attempts were made to extract these compounds from aqueous media using foam columns. Various parameters affecting the retention and separation of these compounds were studied, including temperature, flow-rate, pH, insecticide concentration, shaking time, sample volume and eluting solvent. The complete separation and quantitative recovery of these compounds from the foam with acetone in a Soxhlet extractor were achieved. The method can be used to preconcentrate insecticides in tap water and modified to determine dissolved insecticides in industrial and natural waters. Polyurethane foam has a good capacity for use when large volume samples need to be handled and is an inexpensive sorbent compared to other known solid sorbents.

Iodometric microgram determination of Mn(II) in aqueous media by an indirect chemical amplification reaction.

A rapid, simple and highly sensitive iodometric amplification method is described for the determination of microgram amounts of Mn(II). The method is based on oxidation of Mn(II) with an excess of periodate in acetate buffer (pH 2.8-3.0), masking of the unreacted periodate with molybdate, and after addition of iodide, titration of the liberated iodine is with thiosulphate. The proposed method offers 20-fold amplification for Mn(II) and was found suitable for the determination of Mn(II) in the presence of permanganate ions. Mn(II) in tap water and an industrial waste water has been successfully determined by the proposed method.

Detection and semiquantitative determination of nickel with dimethylglyoxime-loaded foam.

Rapid, sensitive and selective detection and semiquantitative determination of nickel in aqueous solution can be obtained by using dimethylglyoxime loaded on polyurethane foam, either by batch or column extractions, the detection limits being 0.05 and 0.01 ppm respectively.

Simultaneous microdetermination of carbon, hydrogen and chlorine or bromine in organic compounds by various rapid empty-tube combustion methods.

A standard Pregl absorption tube packed with polyurethane foam mixed with a cation-exchanger in the silver form, backed with a layer of "Anhydrone", and connected between the water and carbon dioxide absorption tubes and kept at room temperature, has been employed successfully for the simultaneous determination of chlorine or bromine together with carbon and hydrogen. This foam tube is suitable for use with the Belcher-Ingram, rapid straight empty-tube and rapid flash-combustion methods.

Cellular and foamed plastics as separation media A new geometrical form of the solid phase in analytical liquid-solid contact.

There has been considerable interest during the last few years in using cellular (foamed) plastics (mainly polyurethanes) either unloaded or as a means of immobilizing hydrophobic organic reagents, powdered ion-exchangers or finely divided precipitates, for the collection and separation of inorganic or organic species from aqueous solution. Foamed plastics with anchored (bonded) functional groups have also been used for the same purpose. It has been realized that the application of cellular plastics is often advantageous not only for quantitative work but also for qualitative and semiquantitative analysis. Methods available on the application of cellular and foamed plastics for the collection, separation and recovery of various inorganic and organic components from aqueous solution are reviewed.

Iodometric microdetermination of sulphur in organic compounds by an amplification reaction.

A new method is described for the iodometric microdetermination of sulphur in organic compounds, using a 12-fold amplification reaction after oxygen-flask combustion. The method is based on reaction of the resulting sulphuric add with an excess of saturated barium bromate solution. The unreacted barium bromate is precipitated by addition of acetone, filtered off, redissolved in hot water and after addition of an excess of iodide and acid, the iodine liberated is titrated with thiosulphate. The method is simple, rapid, highly accurate, and of wide application in the microanalysis of organosulphur compounds containing other common acid-forming elements.

Microdetermination of carbon and hydrogen in triterpenoids.

For microdetermination of carbon and hydrogen in triterpenoids, the Vecera, Korshun and Belcher-Ingram rapid methods need modification. In the first method the Co(3)O(4) is activated with 1% NiO, in the second two silica spirals are introduced into the combustion tube, and in the third the sample is covered with Co(3)O(4) powder.