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    Cyto and genotoxicities of graphene oxide and reduced graphene oxide sheets on spermatozoa

    , Article RSC Advances ; Vol. 4, issue. 52 , May , 2014 , pp. 27213-27223 ; ISSN: 20462069 Hashemi, E ; Akhavan, O ; Shamsara, M ; Rahighi, R ; Esfandiar, A ; Tayefeh, A. R ; Sharif University of Technology
    Concentration-dependent cyto and genotoxicities of graphene oxide (GO) and reduced GO (rGO) sheets on spermatozoa were studied. rGO sheets with various surface chemical states were achieved using hydrazine (N2H 4) hydrothermal (HT) reactions and green tea polyphenols (GTPs). Although 0.1 μg mL-1 graphene could not change sperm viability and kinetic parameters, <40% and 20% of spermatozoa were viable and progressively motile, after 2 h incubation with 400 μg mL-1 GO or rGO, respectively. All the graphene nanomaterials induced concentration- dependent reductions of adenosine triphosphate and NAD+/NADH produced by spermatozoa for motility and metabolic activity. While GO, N 2H4-rGO, and HT-rGO... 

    Superhydrophilic stability enhancement of RF co-sputtered TixSi1-xO2 thin films in dark

    , Article Applied Surface Science ; Volume 256, Issue 8 , 2010 , Pages 2500-2506 ; 01694332 (ISSN) Mirshekari, M ; Azimirad, R ; Moshfegh, A. Z ; Sharif University of Technology
    TixSi1-xO2 compound thin-film systems were deposited by reactive RF magnetron co-sputtering technique. The effect of Ti concentration on the hydrophilicity of TixSi1-xO2 compound thin films was studied and it was shown that the films with Ti0.6Si0.4O2 composition possess the best hydrophilic property among all the grown samples. Surface ratio and average roughness of the thin films were measured by atomic force microscopy (AFM). Surface chemical states and stoichiometry of the films were determined by X-ray photoelectron spectroscopy (XPS). In addition, XPS revealed that the amount of Ti-O-Si bonds in nanometer depth from the surface of the Ti0.6Si0.4O2 films was the maximum, which resulted...