Abstract: A method and apparatus for DNA purification are provided which use a silicone structure having a Sio2 layer formed on its surface. In the method, DNA is effectively purified from a fluid sample by maintaining the pH of the silicone structure's surface to be lower than the pKa of silanol to make the surface of the silicone structure charged with hydroxyl groups which results in the binding of DNA present in the fluid sample, removing the residual fluid sample which fails to bind to the surface of the silicone structure, and altering the pH of the silicone structure's surface to be higher than the pKa of silanol to separate the bound DNA from the surface of the silicone structure.