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.

• MeSH
• barvení a značení MeSH
• DNA chemie   MeSH
• fluorescenční barviva chemie   MeSH
• fluorescenční spektrometrie MeSH
• lidé MeSH
• lipidy chemie   MeSH
• organické látky chemie   MeSH
• plazmidy chemie   MeSH
• spermin chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA MeSH
• fluorescenční barviva MeSH
• lipidy MeSH
• organické látky MeSH
• PicoGreen MeSH Prohlížeč
• spermin MeSH