Cadmium nanoparticles citrullinate cytokeratins within lung epithelial cells: cadmium as a potential cause of citrullination in chronic obstructive pulmonary disease.

Objective: The objective of the study was to determine whether the cadmium-derived materials induce intracellular protein citrullination. Methods: Human A549 lung epithelial cells were exposed to cadmium in soluble and nanoparticulate forms represented by cadmium chloride (CdCl2) and cadmium oxide (CdO), respectively, and their combinations with ultrafine carbon black (ufCB) produced by high temperature combustion, imitating cigarette burning. Protein citrullination in cell lysates was analyzed by Western immunoblotting and verified by immunofluorescent confocal microscopy. Target citrullinated proteins were identified by proteomic analysis. Results: CdO, ufCB and its combination with CdCl2 and CdO after high temperature combustion induced protein citrullination in cultured human lung epithelial cells, as detected by immunoblotting with anti-citrullinated protein antibody. Cytokeratins of type II (1, 2, 5, 6A, 6B and 77) and type I (9, 10) were identified as major intracellular citrullination targets. Immunofluorescent staining confirmed the localization of citrullinated proteins both in the cytoplasm and cell nuclei. Conclusion: Cadmium oxide nanoparticle exposure facilitated post-translational citrullination of proteins.

Development of Graphene Nano-Platelet Based Counter Electrodes for Solar Cells.

Graphene has been envisaged as a highly promising material for various field emission devices, supercapacitors, photocatalysts, sensors, electroanalytical systems, fuel cells and photovoltaics. The main goal of our work is to develop new Pt and transparent conductive oxide (TCO) free graphene based counter electrodes (CEs) for dye sensitized solar cells (DSSCs). We have prepared new composites which are based on graphene nano-platelets (GNPs) and conductive polymers such as poly (3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS). Films of these composites were deposited on non-conductive pristine glass substrates and used as CEs for DSSCs which were fabricated by the "open cell" approach. The electrical conductivity studies have clearly demonstrated that the addition of GNPs into PEDOT:PSS films resulted in a significant increase of the electrical conductivity of the composites. The highest solar energy conversion efficiency was achieved for CEs comprising of GNPs with the highest conductivity (190 S/cm) and n-Methyl-2-pyrrolidone (NMP) treated PEDOT:PSS in a composite film. The performance of this cell (4.29% efficiency) compares very favorably to a DSSC with a standard commercially available Pt and TCO based CE (4.72% efficiency in the same type of open DSSC) and is a promising replacement material for the conventional Pt and TCO based CE in DSSCs.

Comparative flow cytometric analysis of immunofunctionalized nanowire and nanoparticle signatures.

Flow cytometry is one of the gold-standard techniques used in clinical medicine for quantitative immunoassaying. The continuous development of its probes, commonly fluorescent nanoparticles, is important. Lately, the introduction of quantitative multiplexed immunoassay has challenged the use of nanoparticles as probes. Functionalized fluorescent silica-based magnetic nanowires are investigated under flow cytometry as a novel probe category. The preparation and full characterization of these multimodal nanowires is reported and compared to those of silica-based magnetic nanoparticles by flow cytometry. Full characterization includes transmission electron microscopy and fluorescence microscopy imaging, flow cytometric assaying, superconducting quantum interference device (SQUID) magnetization, and Mössbauer spectroscopy measurements. This work shows that loaded silica nanowires have intrinsic geometrical advantages when compared to similar spherical particles due to their unique "flow cytometry fingerprint" when utilized as magnetic carriers for immunodetection applications. These advantages account for a 17% yield in detecting the functional binding between THP-1 and ICAM-1, by utilizing a much lower concentration than that required for the nanoparticles.

Third order cascaded Raman wavelength shifting in chalcogenide fibers and determination of Raman gain coefficient.

Cascaded Raman wavelength shifting up to three orders from 1553 nm to 1867 nm is demonstrated in As(2)S(3)-chalcogenide fibers. Due to a long zero dispersion wavelength for the sulfide fiber (>4.5 mum), pumping the fiber at 1553 nm results in generation of cascaded Stokes orders based on stimulated Raman scattering. Using the threshold power for the Raman orders, we estimate the Raman gain coefficient for the As(2)S(3) fibers to be ~5.7x10(-12) m/W at 1550 nm. Observation of higher Raman orders is limited by damage to the fiber at input intensities >1 GW/cm(2).