▎ 摘　　要

The interaction between DNA and graphene-oxide (GO) is fundamental and of significance to a number of biomedical applications. It is fairly clear that pi-pi stacking effect accounts for the strong interaction between ssDNA and GO, while little is known on the mechanics of the relative weak interaction between dsDNA and GO. Here we employ AFM to investigate the coupling behavior of dsDNA-GO duplex and reveal preference adsorption of DNAon GO. The results show that dsDNA tends to aggregate on GO surface. Additionally, it is observed that GO also tend to stack into multi layer structure in the presence of dsDNA, indicating dsDNA can simultaneously interact with two sides of the GO sheet, Such a structure is, however, unstable and can easily collapse by rinsing or heating.