National Chemical Laboratory

About: National Chemical Laboratory is a facility organization based out in Pune, Maharashtra, India. It is known for research contribution in the topics: Catalysis & Nanoparticle. The organization has 8891 authors who have published 14837 publications receiving 387600 citations.

Mast cells migrate, but do not degranulate, in response to fractalkine, a membrane-bound chemokine expressed constitutively in diverse cells of the skin.

Abstract: Mast cells (MC) are anatomically located near nerves and blood vessels in skin and the gastrointestinal tract and tend to localize within certain cutaneous tumors such as neurofibromas. However, the molecular mechanisms by which MC home to these sites are not well characterized. Fractalkine (FK) is a membrane-bound CX3C chemokine that displays constitutive expression in dendritic cells as well as in non-hematopoietic tissues including mammalian brain. Here we show that FK is constitutively expressed by skin endothelial cells, dermal dendrocytes and cells within neurofibromas. By reverse transcription-PCR, FK receptor, CX3CR1, is expressed by cultured murine bone marrow-derived MC (BMMC) of both connective tissue and mucosal phenotypes. Non-activated human dermal MC isolated from neonatal foreskin similarly demonstrated CX3CR1 expression. In chemotaxis assays, FK attracted MC with maximal migration occurring between 25 - 125 ng / ml. BMMC were not stimulated to release proinflammatory mediators in the presence of FK as measured by granule-associated beta-hexosaminidase release. Thus, CX3CR1 is expressed by MC and effectively mediates chemotaxis without inducing degranulation. We propose that the constitutive expression of FK on certain cells in the skin may be a factor in the tissue-specific homing of MC.

An Ultrahydrophobic Fluorous Metal-Organic Framework Derived Recyclable Composite as a Promising Platform to Tackle Marine Oil Spills.

Abstract: Derived from a strategically chosen hexafluorinated dicarboxylate linker aimed at the designed synthesis of a superhydrophobic metal-organic framework (MOF), the fluorine-rich nanospace of a water-stable MOF (UHMOF-100) exhibits excellent water-repellent features. It registered the highest water contact angle (≈176°) in the MOF domain, marking the first example of an ultrahydrophobic MOF. Various experimental and theoretical studies reinforce its distinctive water-repellent characteristics, and the conjugation of superoleophilicity and unparalleled hydrophobicity of a MOF material has been coherently exploited to achieve real-time oil/water separation in recyclable membrane form, with significant absorption capacity performance. This is also the first report of an oil/water separating fluorinated ultrahydrophobic MOF-based membrane material, with potential promise for tackling marine oil spillages.

Sulfur Nanoparticles Synthesis and Characterization from H2S Gas, Using Novel Biodegradable Iron Chelates in W/O Microemulsion

Abstract: Sulfur nanoparticles were synthesized from hazardous H2S gas using novel biodegradable iron chelates in w/o microemulsion system. Fe3+–malic acid chelate (0.05 M aqueous solution) was studied in w/o microemulsion containing cyclohexane, Triton X-100 andn-hexanol as oil phase, surfactant, co-surfactant, respectively, for catalytic oxidation of H2S gas at ambient conditions of temperature, pressure, and neutral pH. The structural features of sulfur nanoparticles have been characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), energy dispersive spectroscopy (EDS), diffused reflectance infra-red Fourier transform technique, and BET surface area measurements. XRD analysis indicates the presence of α-sulfur. TEM analysis shows that the morphology of sulfur nanoparticles synthesized in w/o microemulsion system is nearly uniform in size (average particle size 10 nm) and narrow particle size distribution (in range of 5–15 nm) as compared to that in aqueous surfactant systems. The EDS analysis indicated high purity of sulfur (>99%). Moreover, sulfur nanoparticles synthesized in w/o microemulsion system exhibit higher antimicrobial activity (against bacteria, yeast, and fungi) than that of colloidal sulfur.

Preparation, Characterization, and Performance of Conductive Fabrics: Cotton + PANi

Abstract: Conductive cotton + PANi fabrics are prepared by in-situ chemical oxidative polymer ization of aniline using ammonium persulphate as the oxidant by a process of diffusion polymerization in a mixed bath. These fabrics are characterized by elemental analysis, XRF, ATR-FTIR, WAXD, SEM, DSC, and two-probe conductivity. Sorption properties are studied by measuring the weight uptake before and after reaction. The composite fabrics are studied for their performance after repeated washing, and tested for their flame retardancy, EMI shielding, and gas sensing properties.