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Singlet oxygen generation from water-soluble quantum dot-organic dye nanocomposites.

ABSTRACT: Water-soluble quantum dot-organic dye nanocomposites have been prepared via electrostatic interaction. We used CdTe quantum dots with diameters up to 3.4 nm, 2-aminoethanethiol as a stabilizer, and meso-tetra(4-sulfonatophenyl)porphine dihydrochloride (TSPP) as an organic dye. The photophysical properties of the nanocomposite have been investigated. The fluorescence of the parent CdTe quantum dot is largely suppressed. Instead, indirect excitation of the TSPP moiety leads to production of singlet oxygen with a quantum yield of 0.43. The nanocomposite is sufficiently photostable for biological applications.

SUBMITTER: Shi L

PROVIDER: S-EPMC3164884 | biostudies-literature | 2006 May

REPOSITORIES: biostudies-literature

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Singlet oxygen generation from water-soluble quantum dot-organic dye nanocomposites.

Shi Lixin L Hernandez Billy B Selke Matthias M

Journal of the American Chemical Society 20060501 19

Water-soluble quantum dot-organic dye nanocomposites have been prepared via electrostatic interaction. We used CdTe quantum dots with diameters up to 3.4 nm, 2-aminoethanethiol as a stabilizer, and meso-tetra(4-sulfonatophenyl)porphine dihydrochloride (TSPP) as an organic dye. The photophysical properties of the nanocomposite have been investigated. The fluorescence of the parent CdTe quantum dot is largely suppressed. Instead, indirect excitation of the TSPP moiety leads to production of single ...[more]

PMID: 16683767

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