Patent ID: 6881317

Claim:
A method of continuously fractionating charged macro-molecules comprising: loading molecules into a matrix of obstacles; applying an asymmetric electric field to the matrix to separate the molecules according to size along a horizontal direction of the matrix; and collecting separated molecules at a plurality of locations along a bottom edge of the matrix, wherein the step of applying an asymmetric electric field to the matrix comprises applying an electric field which is alternating in direction as a function of time at a location in the matrix, and which has a time average of an electric field vector over many cycles, whereby the time integral of the vector at the same location over a part of the cycles when the electric field is instantaneously pointing to one side of the vector is not spatially symmetric about the vector with the time integral of the vector over another part of the cycles at the same location when the electric field is instantaneously pointing to another side of the vector.