Flexible fluorescently labelled colloidal bead chains: synthesis and their real-space studies

Abstract

A quest for colloidal particles with more complex shapes and interactions is fueled by applications in self-assembly and advanced functional material design, but also by the demand for more realistic model systems for molecular analogues. Recently, Vutukuri et al. introduced a simple method to produce model system of colloidal analogues of (bio-)polymer chains with a tunable flexibility from dielectric colloids using AC electric fields and a simple bonding step [1, 2]. In this thesis we first discuss a method for transferring sterically stabilized and fluorescently labeled PMMA particles from a polar solvent to different solvents with the optional use of surfactants as in [3, 4]. To facilitate optimal imaging conditions for confocal laser scanning microscopy we focused on solvents that are similar in refractive index to PMMA. The resulting dispersions were exposed to high frequency AC electric fields in order to align the particles in strings, followed by the earlier mentioned simple in situ thermal annealing step [1]. We analyzed the permanent strings with feature finding and tracking software quantitatively in 2D and qualitatively in 3D.

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