Regensburg 2004 – scientific programme
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CPP: Chemische Physik und Polymerphysik
CPP 16: POSTER: Computational Physics, Complex Systems
CPP 16.30: Poster
Tuesday, March 9, 2004, 17:00–19:00, B
Fluorescence Correlation Spectroscopy Investigations of Water-soluble Polymers — •Tune B. Bonné1, Karin Lüdtke2, Rainer Jordan2, Petr Štěpánek3, and Christine M. Papadakis1 — 1Faculty of Physics and Earth Sciences, University of Leipzig, D-04103 Leipzig, Germany — 2Faculty of Chemistry, Technische Universität München, D-85747 Garching, Germany — 3Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague
Fluorescence correlation spectroscopy (FCS) is a method to study the
self-diffusion of fluorescence-labeled molecules. The detection volume is
very small (∼ 1 µm3), and the measurements are carried out on
the basis of very few molecules in the detection volume.
Using FCS, we have studied the micellization of fluorescence-labeled
poly(methyloxazoline)-poly(nonyloxazoline) diblock copolymers in aqueous
solution. This polymer system is very versatile with respect to the degree
of hydrophobicity of the blocks. In order to investigate the influence of
the dye on the aggregation behavior, polymers with the dye attached to
either the hydrophilic or the hydrophobic end were investigated. The
critical micelle concentrations were determined with FCS. By comparing with
results from dynamic light scattering (DLS), it is shown that the
hydrodynamic radius of the micelles can reliably be determined using FCS.
Temperature-resolved DLS showed, however, that after dissolution of the
polymers in water at room temperature, large aggregates are formed, and
stable micelles form only after heating the solutions.