Teresa Kral1, Marek Langner, Martin Hof. 1. J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic. tek@ozi.ar.wroc.pl
Abstract
BACKGROUND: Fluorescence correlation spectroscopy (FCS) can be used for the determination of diffusion coefficients of single molecules. Since diffusion coefficients are correlated with size and shape of the labeled species, FCS provides information on conformational changes in plasmids aggregates. METHODS: A 10-kbp plasmid stained with PicoGreen was condensed by spermine or liposomes formulated from cationic lipid and egg phosphatidylcholine. RESULTS: The diffusion coefficient of DNA increases from 1.0 x 10(-12) m2/s to 3.2 x 10(-12) m2/s by the addition of spermine, whereas the addition of cationic liposomes leads to complexes characterized by diffusion coefficients with values ranging from 1.7 to 1.9 x 10(-12) m2/s. CONCLUSIONS: FCS experiments allow determining the diffusion coefficients of DNA-containing aggregates which provide information regarding the topology and homogeneity of the aggregate.
BACKGROUND: Fluorescence correlation spectroscopy (FCS) can be used for the determination of diffusion coefficients of single molecules. Since diffusion coefficients are correlated with size and shape of the labeled species, FCS provides information on conformational changes in plasmids aggregates. METHODS: A 10-kbp plasmid stained with PicoGreen was condensed by spermine or liposomes formulated from cationic lipid and egg phosphatidylcholine. RESULTS: The diffusion coefficient of DNA increases from 1.0 x 10(-12) m2/s to 3.2 x 10(-12) m2/s by the addition of spermine, whereas the addition of cationic liposomes leads to complexes characterized by diffusion coefficients with values ranging from 1.7 to 1.9 x 10(-12) m2/s. CONCLUSIONS: FCS experiments allow determining the diffusion coefficients of DNA-containing aggregates which provide information regarding the topology and homogeneity of the aggregate.
Authors: Jana Humpolícková; Ales Benda; Jan Sýkora; Radek Machán; Teresa Kral; Barbara Gasinska; Joerg Enderlein; Martin Hof Journal: Biophys J Date: 2007-10-26 Impact factor: 4.033
Authors: Jana Humpolícková; Miroslav Stepánek; Teresa Kral; Ales Benda; Karel Procházka; Martin Hof Journal: J Fluoresc Date: 2008-02-15 Impact factor: 2.217