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Permeability of anti-fouling PEGylated surfaces probed by fluorescence correlation spectroscopy.

ABSTRACT: The present work reports on in situ observations of the interaction of organic dye probe molecules and dye-labeled protein with different poly(ethylene glycol) (PEG) architectures (linear, dendron, and bottle brush). Fluorescence correlation spectroscopy (FCS) and single molecule event analysis were used to examine the nature and extent of probe-PEG interactions. The data support a sieve-like model in which size-exclusion principles determine the extent of probe-PEG interactions. Small probes are trapped by more dense PEG architectures and large probes interact more with less dense PEG surfaces. These results, and the tunable pore structure of the PEG dendrons employed in this work, suggest the viability of electrochemically-active materials for tunable surfaces.

SUBMITTER: Daniels CR

PROVIDER: S-EPMC5625349 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Permeability of anti-fouling PEGylated surfaces probed by fluorescence correlation spectroscopy.

Daniels Charlisa R CR Reznik Carmen C Kilmer Rachel R Felipe Mary Jane MJ Tria Maria Celeste R MC Kourentzi Katerina K Chen Wen-Hsiang WH Advincula Rigoberto C RC Willson Richard C RC Landes Christy F CF

Colloids and surfaces. B, Biointerfaces 20110527 1

The present work reports on in situ observations of the interaction of organic dye probe molecules and dye-labeled protein with different poly(ethylene glycol) (PEG) architectures (linear, dendron, and bottle brush). Fluorescence correlation spectroscopy (FCS) and single molecule event analysis were used to examine the nature and extent of probe-PEG interactions. The data support a sieve-like model in which size-exclusion principles determine the extent of probe-PEG interactions. Small probes ar ...[more]

PMID: 21742471

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