Differential transport of DNA by a rectified Brownian motion device

An interdigitated electrode array (IDEA) device has been designed and used to transport DNA based on a Brownian ratchet mechanism This migration is pr oduced by the periodic formation of an asymmetric sawtooth electric field i n the device. Oligonucleotides of 25, 50, and 100 bases In length were test ed using two different array geometries. DNA transport as a function of DNA size, electric field frequency, and array geometry is shown to be in quali tative agreement with theory. Such a device could provide for DNA separatio ns over a broad size range, and can be readily scaled as a component in a m icrofabricated DNA analysis system.