Investigating the Interactions between DNA Oligomers and Gemini Surfactants

The observation that, under certain condition, a precipitate forms in a solution of (TTAGGG)4 and a 12-4-12 Gemini surfactant led us to expand the investigation. In the initial studies, solutions were prepared that contained a fixed concentration of the DNA oligomer Poster Presentations 20 and concentrations of the surfactant ranging from 0 mM to 3 mM – hence below and above the cmc of the surfactant (1.0 mM). The amount of DNA that precipitated depended upon the concentration of surfactant: at concentrations of surfactant above its cmc, all of the DNA was removed from solution; at concentrations below the cmc, some DNA precipitated but some DNA was still in solution. Thus, we began a systematic study into this phenomenon using circular dichroism (CD), UV/vis and conductivity studies. Solutions of different DNA oligomer sequences and surfactants were prepared to examine DNA sequence context and environmental effects leading to zero, partial precipitation or total precipitation of the DNA. A progress report of these studies will be presented.