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Updated: May 13, 2026
07:41
Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging
Published on: July 19, 2016
7.7K
Understanding associative polymer self-assembly with shrinking gate fluorescence correlation spectroscopy.
Timothy J Murdoch1, Baptiste Quienne2, Julien Pinaud2
1Department of Materials, Loughborough University, LE11 1RJ Loughborough, UK. i.martin-fabiani@lboro.ac.uk.
Nanoscale
|June 18, 2024
Summary
This study uses a novel fluorescence method to track polymer self-assembly in liquids. It reveals how hydrophobically modified ethoxylated urethane (HEUR) forms aggregates and networks, crucial for liquid formulations.
Area of Science:
- Polymer Science
- Materials Chemistry
- Physical Chemistry
Background:
- Polymer self-assembly is critical for liquid formulations.
- Understanding polymer aggregation dynamics is essential for material design.
Purpose of the Study:
- To investigate the self-assembly of hydrophobically modified ethoxylated urethane (HEUR) polymers.
- To apply shrinking gate fluorescence correlation spectroscopy (sgFCS) for polymer dynamics analysis.
- To characterize the formation of micellar aggregates and percolated networks in HEUR solutions.
Main Methods:
- Utilized a fluorescence dye sensitive to local nanoviscosity.
- Employed shrinking gate fluorescence correlation spectroscopy (sgFCS) to isolate bound dye dynamics.
- Analyzed fluorescence lifetime measurements to correlate with polymer concentration.
Main Results:
- Identified a small fraction of dye (<1%) strongly bound to HEUR, influencing fluorescence lifetime.
- sgFCS successfully isolated the diffusional dynamics of the bound dye fraction.
- Observed micellar aggregate formation between 0.2-1 wt% HEUR, followed by network percolation.
Conclusions:
- sgFCS offers enhanced sensitivity for studying polymer self-assembly compared to standard FCS.
- The method is adaptable for any dye exhibiting lifetime changes upon binding.
- This technique provides new insights into polymer aggregation and network formation in liquid formulations.
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