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Singlet oxygen production by Peptide-coated quantum dot-photosensitizer conjugates.

ABSTRACT: Peptide-coated quantum dot-photosensitizer conjugates were developed using novel covalent conjugation strategies on peptides which overcoat quantum dots (QDs). Rose bengal and chlorin e6, photosensitizers (PSs) that generate singlet oxygen in high yield, were covalently attached to phytochelatin-related peptides. The photosensitizer-peptide conjugates were subsequently used to overcoat green- and red-emitting CdSe/CdS/ZnS nanocrystals. Generation of singlet oxygen could be achieved via indirect excitation through Förster (fluorescence) resonance energy transfer (FRET) from the nanocrystals to PSs, or by direct excitation of the PSs. In the latter case, by using two color excitations, the conjugate could be simultaneously used for fluorescence imaging and singlet oxygen generation. Singlet oxygen quantum yields as high as 0.31 were achieved using 532-nm excitation wavelengths.

SUBMITTER: Tsay JM

PROVIDER: S-EPMC2527466 | biostudies-literature | 2007 May

REPOSITORIES: biostudies-literature

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Singlet oxygen production by Peptide-coated quantum dot-photosensitizer conjugates.

Tsay James M JM Trzoss Michael M Shi Lixin L Kong Xiangxu X Selke Matthias M Jung Michael E ME Weiss Shimon S

Journal of the American Chemical Society 20070504 21

Peptide-coated quantum dot-photosensitizer conjugates were developed using novel covalent conjugation strategies on peptides which overcoat quantum dots (QDs). Rose bengal and chlorin e6, photosensitizers (PSs) that generate singlet oxygen in high yield, were covalently attached to phytochelatin-related peptides. The photosensitizer-peptide conjugates were subsequently used to overcoat green- and red-emitting CdSe/CdS/ZnS nanocrystals. Generation of singlet oxygen could be achieved via indirect ...[more]

PMID: 17477530

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