In Situ Fluorescence Microscope Measurements of the Phase Transfer Dynamics of Single DNA Molecular Ions with Dimethyldioctadecylammonium Chloride into Isooctane–1-Octanol Mixture

Abstract

The solvent extraction of single giant DNA molecular ions by N,N-dimethyl-N,N-dioctadecylammonium chloride was investigated under a fluorescence microscope with high resolution and their phase transfers from the water phase to the isooctane–1-octanol mixture (oil) phase were observed successfully. DNAs in the water phase were in the random-coil state, and those extracted in the oil phase were in the imperfect globule state, whereas those existing at the interface were almost in the globule state. From these conformation changes, the phase transfer mechanism of DNA at the interface was proposed.