DNA size separation using artificially nanostructured matrix

We have demonstrated two types of size separation of biomolecules using a nanostructured matrix artificially fabricated using electron-beam lithography: sieve-type separation using a regular pillar array structure and size exclusion chromatography (SEC) type separation using a structure with narrow and wide gaps. With these devices, samples of double-stranded DNA molecules (2, 5, and 10 k base pairs) were clearly separated into bands; smaller molecules eluted earlier in the sieve type while they eluted later in the SEC type. The nanostructured matrix enables various types of molecular separation by changing the design of the nanostructure. Moreover, it should be easy to integrate the matrix with other biomolecular fluidic devices because it does not require a filling medium.