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Sizing subcellular organelles and nanoparticles confined within aqueous droplets.

ABSTRACT: This article describes two complementary techniques, single-particle tracking and correlation spectroscopy, for accurately sizing nanoparticles confined within picoliter volume aqueous droplets. Single-particle tracking works well with bright particles that can be continuously illuminated and imaged, and we demonstrated this approach for sizing single fluorescent beads. Fluorescence correlation spectroscopy detects small intensity bursts from particles or molecules diffusing through the confocal probe volume, which works well with dim and rapidly diffusing particles or molecules; we demonstrated FCS for sizing synaptic vesicles confined in aqueous droplets. In combination with recent advances in droplet manipulations and analysis, we anticipate this capability to size single nanoparticles and molecules in free solution will complement existing tools for probing cellular systems, subcellular organelles, and nanoparticles.

SUBMITTER: Gadd JC

PROVIDER: S-EPMC2692466 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Sizing subcellular organelles and nanoparticles confined within aqueous droplets.

Gadd Jennifer C JC Kuyper Christopher L CL Fujimoto Bryant S BS Allen Richard W RW Chiu Daniel T DT

Analytical chemistry 20080326 9

This article describes two complementary techniques, single-particle tracking and correlation spectroscopy, for accurately sizing nanoparticles confined within picoliter volume aqueous droplets. Single-particle tracking works well with bright particles that can be continuously illuminated and imaged, and we demonstrated this approach for sizing single fluorescent beads. Fluorescence correlation spectroscopy detects small intensity bursts from particles or molecules diffusing through the confocal ...[more]

PMID: 18363409

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