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An effective and green method including in-situ solvothermal reduction of multi-layered graphene oxide (MLGO) using a mixture of acetonitrile and sesame, ginger and cinnamon oils, was investigated for preparing a hydrophobic and corrosion-resistant epoxy coating. The efficiencies of the oils as green reducing agents with synergistic effect by acetonitrile in the solvothermal reduction of MLGO at a temperature of 70 °C were compared with each other. FT-IR, TGA, Raman, and Mapping-EDAX analysis showed that the solvothermal reduction process of MLGO in acetonitrile/cinnamon oil mixture was successfully performed. The results of long-term salt spray and electrochemical impedance tests showed that epoxy-RMLGO (acetonitrile/cinnamon oil) nano-coating had a significant improvement in corrosion resistance (after10 months, the impedance value was 8.1 × 108 Ω cm2) compared with the other coatings. Also, the value of the water contact angle for the nano-coating was 102.80° and based on Mapping-EDAX analysis, the C/O ratio was 54.45. [ABSTRACT FROM AUTHOR]

Hydro-thermal synthesised MOWS2 nano-composite has been specified and employed to the modify a screen-printed electrode (SPE) in electro-catalytic voltammetric detection of hydroxylamine. Sensor of MOWS2 nano-composite has been followed by acceptable function to detect hydroxylamine with a linear range within 0.7–400.0 µM, and a limit of detection (LOD) of 0.2 µM. Results indicated that MOWS2 nano-composite enjoy high potentials to be used in electrochemical sensing. Moreover, this modified electrode has the benefits of a significant linear association, higher sensitivity and small determination limit, acceptable anti-interference capability and very high stability, resulting in widespread uses in detecting real samples. [ABSTRACT FROM AUTHOR]

A modified carbon paste electrode has been developed for the determination of Pb(ΙΙ) ions based on Fe3O4/eggshell magnetic nanocomposite. The structure and morphology of Fe3O4/eggshell were analysed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The prepared nanocomposite was also characterized by Fourier transform infrared spectroscopy (FT-IR) and vibrating sample magnetometer (VSM). The electrochemical procedure was based on the accumulation and determination of Pb(ΙΙ) ions at the surface of the modified carbon paste electrode with Fe3O4/eggshell nanocomposites and carbon nanotubes by differential pulse anodic stripping voltammetry (DPASV). Various experimental parameters involved in the preconcentration of Pb(ΙΙ) ions and voltammetric stripping step were studied. Under the optimum conditions, the voltammetric peak current of Pb(ΙΙ) occurs at a potential about −0.5 V. Also, the voltammetric peak current increased linearly with Pb(ΙΙ) concentration in the range of 0.5–200 ng mL−1 and a detection limit of 0.15 ng mL−1 was obtained for Pb(ΙΙ). The selectivity of the proposed electrode for Pb(ΙΙ) ions in the presence of some cations was also examined. The practical application of the proposed modified electrode was evaluated by the determination of Pb(ΙΙ) ions in human hair and water samples. The results were satisfactory for the spiked samples. [ABSTRACT FROM AUTHOR]

Tripolyphosphate corrosion inhibitor was modified by functionalized graphite nanoplatelets to obtain a hybrid nanoparticle (functionalized graphite nanoplatelets–tripolyphosphate) with homogenous dispersion in epoxy coating. The effect of functionalized graphite nanoplatelets–tripolyphosphate dispersion on adhesion and anticorrosion behavior was discussed. Characterization analyses of the hybrid nanoparticle were performed by Fourier transform-infrared spectroscope, scanning electron microscope, and transmission electron microscope. Tripolyphosphate was linked to functionalized graphite nanoparticles by hydrogen bondings. Different epoxy coatings formulated with 1 wt% of functionalized graphite nanoplatelets, functionalized graphite nanoplatelets–tripolyphosphate, and tripolyphosphate were evaluated. Results showed, compared to traditional phosphate pigments, the adhesion of functionalized graphite nanoplatelets–tripolyphosphate epoxy coating and its anticorrosion behavior were significantly increased with the lowest loadings amounts. [ABSTRACT FROM PUBLISHER]

In this study, a novel sample clean-up technique based on the molecularly imprinted solid-phase extraction (MISPE) procedure is described for the determination of dipyridamole (DIP) in biological fluids. The water-compatible molecularly imprinted polymers (MIPs) were prepared using methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, and DIP as the template molecule in chloroform. The novel imprinted polymer was used as a solid-phase extraction sorbent for the extraction of DIP from human serum and urine. Various parameters affecting the extraction efficiency of the polymer were evaluated. The optimal conditions for molecularly imprinted solid-phase extraction of the cartridges were obtained. The MIP selectivity was evaluated by checking several substances with similar molecular structures to the template. The limit of detection (LOD) and limit of quantification (LOQ) for DIP in urine samples were 1.6 and 4.0 µg L−1, respectively. These limits for DIP in serum samples were 2.5 and 6.2 µg L−1, respectively. The recoveries for serum and urine samples were higher than 80.0 and 83.0%, respectively. [ABSTRACT FROM PUBLISHER]