Government College

About: Government College is a based out in . It is known for research contribution in the topics: Population & Ring (chemistry). The organization has 4481 authors who have published 5986 publications receiving 57398 citations.

Efficient room temperature methanol sensors based on polyaniline/graphene micro/nanocomposites

Abstract: The chemically prepared pristine and graphene-doped polyaniline (PANI) samples are utilized for the fabrication of room temperature methanol sensors. For the fabrication of PANI/graphene-based sensing devices, four samples of PANI/graphene composites were prepared with four different concentrations of graphene (2, 4, 6 and 8 wt%). The surface morphology of the prepared composites was analyzed under field emission scanning electron microscopy (FE-SEM), which revealed the agglomerated structures of PANI/graphene composites. X-Ray diffraction studies carried out on these samples revealed the semi-crystalline nature of the samples, whereas, Raman studies confirmed the growth of PANI with the presence of all fundamental bands of PANI in the pristine as well as in its doped state. The prepared PANI/graphene composites devices were tested for alcohol detection at two different concentrations (50 and 100 ppm) of methanol. The change in electric current with the change in environment has been recorded as a sensing parameter and is employed to determine other sensor parameters such as percentage response, response time and recovery time. The sensing response of the prepared samples is found to increase with graphene doping concentration as well as methanol ppm level. The PANI/graphene composite with 8 wt% doping of graphene has shown the highest response (~ 61.5% at 100 ppm) and the lowest response time (55 s). The mechanism of gas sensing has also been discussed in details with the possible theoretical analogy with the adsorption and desorption of gas molecules in accordance with Langmuir kinetic theory.

An In Vitro Study of the Photodynamic Effectiveness of GO-Ag Nanocomposites against Human Breast Cancer Cells.

Abstract: Graphene-based materials have garnered significant attention because of their versatile bioapplications and extraordinary properties. Graphene oxide (GO) is an extremely oxidized form of graphene accompanied by the functional groups of oxygen on its surface. GO is an outstanding platform on which to pacify silver nanoparticles (Ag NPs), which gives rise to the graphene oxide-silver nanoparticle (GO-Ag) nanocomposite. In this experimental study, the toxicity of graphene oxide-silver (GO-Ag) nanocomposites was assessed in an in vitro human breast cancer model to optimize the parameters of photodynamic therapy. GO-Ag was prepared using the hydrothermal method, and characterization was done by X-ray diffraction, field-emission scanning electron microscope (FE-SEM), transmission Electron Microscopy (TEM), energy dispersive X-rays Analysis (EDAX), atomic force microscopy and ultraviolet-visible spectroscopy. The experiments were done both with laser exposure, as well as in darkness, to examine the phototoxicity and cytotoxicity of the nanocomposites. The cytotoxicity of the GO-Ag was confirmed via a methyl-thiazole-tetrazolium (MTT) assay and intracellular reactive oxygen species production analysis. The phototoxic effect explored the dose-dependent decrease in the cell viability, as well as provoked cell death via apoptosis. An enormously significant escalation of 1O2 in the samples when exposed to daylight was perceived. Statistical analysis was performed on the experimental results to confirm the worth and clarity of the results, with p-values < 0.05 selected as significant. These outcomes suggest that GO-Ag nanocomposites could serve as potential candidates for targeted breast cancer therapy.

Rapid and sensitive spectrophotometric determination of trace amounts of iron(III) using leuco Xylene cyanol FF

Abstract: A new, simple, sensitive, and reliable method is presented for the rapid spectrophotometric determination of trace amounts of iron(III) using leuco Xylene cyanol FF. The method is based on the oxidation of leuco Xylene cyanol FF (LXCFF) to its blue form of xylene cyanol FF by iron(III) in sulfuric acid medium (pH 2.0–3.0), the absorbance of the formed dye is measured in an acetate buffer medium (pH 2.8–4.4) at 615 nm. The method obeys Beer's law over a concentration range of 0.15–0.9 μg mL-1 iron, having a molar absorptivity of 5.6×104 L mol-1 cm-1 and a Sandell's sensitivity of 0.0001 μg cm-2. The optimum reaction conditions and other analytical parameters have been evaluated. The developed method has been successfully applied to the determination of iron in water, soil, industrial effluent, plant material, pharmaceutical preparations, synthetic mixtures, and aluminum alloys.