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Stable, small, specific, low-valency quantum dots for single-molecule imaging.

ABSTRACT: We have developed a strategy for synthesizing immediately activable, water-soluble, compact (?10-12 nm hydrodynamic diameter) quantum dots with a small number of stable and controllable conjugation handles for long distance delivery and subsequent biomolecule conjugation. Upon covalent conjugation with engineered monovalent streptavidin, the sample results in a population consisting of low-valency quantum dots. Alternatively, we have synthesized quantum dots with a small number of biotin molecules that can self-assemble with engineered divalent streptavidin via high-affinity biotin-streptavidin interactions. Being compact, stable and highly specific against biotinylated proteins of interest, these low-valency quantum dots are ideal for labeling and tracking single molecules on the cell surface with high spatiotemporal resolution for different biological systems and applications.

SUBMITTER: Lee J

PROVIDER: S-EPMC5866912 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Stable, small, specific, low-valency quantum dots for single-molecule imaging.

Lee Jungmin J Feng Xinyi X Chen Ou O Bawendi Moungi G MG Huang Jun J

Nanoscale 20180301 9

We have developed a strategy for synthesizing immediately activable, water-soluble, compact (∼10-12 nm hydrodynamic diameter) quantum dots with a small number of stable and controllable conjugation handles for long distance delivery and subsequent biomolecule conjugation. Upon covalent conjugation with engineered monovalent streptavidin, the sample results in a population consisting of low-valency quantum dots. Alternatively, we have synthesized quantum dots with a small number of biotin molecul ...[more]

PMID: 29451567

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