Interaction energy between each modified DNA and chloroform/water. (A) me-bz-DNA and chloroform. (B) me-bz-DNA and water. (C) me-DNA and chloroform. (D) me-DNA and water. (E) bz-DNA and chloroform. (F) bz-DNA and water. (G) DX-DNA and chloroform. (H) DX-DNA and water. In this figure, chl-elec represents electrostatic interaction energy between DNA and chloroform, chl-vdw represents van der Waals interaction energy between DNA and chloroform, chl-total represents electrostatic interaction energy plus van der Waals energy between DNA and chloroform, wat-elec represents electrostatic interaction energy between DNA and water, wat-vdw represents van der Waals interaction energy between DNA and water, and wat-total represents electrostatic interaction energy plus van der Waals energy between DNA and water.