Polyelectrolyte-compression forces between spherical DNA brushes.
Optical tweezers are employed to measure the forces of interaction within a single pair of DNA-grafted colloids, dependent on 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 relation is analyzed by means of a theoretical treatment that quantitatively describes the effects of compression of the chains on the surface of the opposite-lying colloid. Quantitative agreement with the experiment is obtained for all parameter combinations.
Kegler
Kati
K
Institute for Experimental Physics I, University of Leipzig, Linéestrasse 5, D-04103 Leipzig, Germany.
Konieczny
Martin
M
Dominguez-Espinosa
Gustavo
G
Gutsche
Christof
C
Salomo
Matthias
M
Kremer
Friedrich
F
Likos
Christos N
CN
D020029:Base Pairing; D003102:Colloids; D004247:DNA / Q000737:chemistry*; D004573:Electrolytes / Q000737:chemistry*; D008956:Models, Chemical; D009690:Nucleic Acid Conformation; D052898:Optical Tweezers; D014867:Water / Q000737:chemistry
D003102:Colloids; D004573:Electrolytes; D014867:Water; D004247:DNA