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arXiv · 0710.0303

Polyelectrolyte-Compression Forces between Spherical DNA Brushes

Kati Kegler·Martin Konieczny·Gustavo Dominguez-Espinoza·Christof Gutsche·Matthias Salomo·Friedrich Kremer·Christos N. Likos
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Abstract

Optical tweezers are employed to measure the forces of interaction within a single pair of DNA-grafted colloids in dependence of the molecular weight of the DNA-chains, and the concentration and valence of the surrounding ionic medium. The resulting forces are short-range and set in as the surface-to-surface distance between the colloidal cores reaches the value of the brush height. The measured force-distance dependence is analyzed by means of a theoretical treatment based on the compression of the chains on the surface of the opposite-lying colloid. Quantitative agreement with the experiment is obtained for all parameter combinations.

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Kati Kegler, Martin Konieczny, Gustavo Dominguez-Espinoza, Christof Gutsche, Matthias Salomo, Friedrich Kremer, Christos N. Likos. 2007-10-01. Polyelectrolyte-Compression Forces between Spherical DNA Brushes. https://doi.org/10.1103/physrevlett.100.118302

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