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The optical properties of gold nanoparticles with dopamine at different hydrogen ion concentration.

The optical properties of gold nanoparticles with dopamine at different hydrogen ion concentration.

Journal of nanoscience and nanotechnology (2013-07-19)

Yanru Bu, Sangwha Lee

ABSTRACT

In this work, gold nanoparticles (Au NPs) were prepared by citrate reduction method, and the Surface-Enhanced Raman Scattering (SERS) intensities of these colloidal solutions with dopamine (DA) were compared at different hydrogen ion concentration (pH). The charged states of Au NPs and DA molecules at different pH were critical factors for the SERS intensity by affecting NPs aggregation degree via DA bridging-effect. The results showed that the SERS enhancement was strongest at intermediate pH ranges (pH 7-9), in which the Au NPs was sufficiently stable and the electrostatic interaction between the Au NPs and the DA molecules was appropriate, together with a slightly aggregating.

MATERIALI

N° Catalogo

Marchio

Descrizione del prodotto

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Hydrogen, ≥99.99%

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Gold, powder, <45 μm, 99.99% trace metals basis

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Gold, nanopowder, <100 nm particle size, 99.9% trace metals basis

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Gold, powder, <10 μm, ≥99.9% trace metals basis

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Gold coated glass slide, 99.999% (Au), layer thickness 100 Å

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Gold, foil, thickness 0.1 mm, 99.99% trace metals basis

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Gold, wire, diam. 1.0 mm, 99.99% trace metals basis

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Gold, wire, diam. 0.25 mm, ≥99.9% trace metals basis

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Gold, foil, thickness 0.5 mm, 99.99% trace metals basis

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Gold, beads, 1-6 mm, 99.999% trace metals basis

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Gold coated glass cover slip, 99.999% (Au), layer thickness 100 Å, L × W × thickness 22 mm × 22 mm × 130-170 μm, square

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Gold, evaporation slug, diam. × L 0.3 cm × 0.6 cm, 99.99% trace metals basis

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Gold, wire, diam. 0.1 mm, 99.99% trace metals basis

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Gold coated glass slide, 99.999% (Au), layer thickness 1000 Å

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Gold, foil, thickness 0.05 mm, 99.99% trace metals basis

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Gold, rod, diam. 3.0 mm, 99.99% trace metals basis

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Gold, foil, thickness 0.025 mm, 99.99% trace metals basis

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Gold, wire, diam. 0.5 mm, 99.99% trace metals basis

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Gold, foil, thickness 0.127 mm, 99.99% trace metals basis

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Gold, foil, thickness 0.25 mm, ≥99.9% trace metals basis

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Gold, wire, diam. 0.25 mm, 99.99% trace metals basis

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Gold, powder, <850 μm, ≥99.99% trace metals basis

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Gold, evaporation slug, diam. × L 0.6 cm × 0.6 cm, 99.99% trace metals basis

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Gold, wire, diam. 1.0 mm, 99.997% trace metals basis

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Gold, wire, diam. 0.5 mm, 99.999% trace metals basis

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Gold coated glass cover slip, 99.999% (Au), diam. × thickness 15 mm × 130-170 μm, layer thickness 100 Å

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Gold, wire, diam. 0.127 mm, 99.99% trace metals basis