Method of electric field flow fractionation wherein the polarity of the electric field is periodically reversed
AssigneeUnited States Department of Energy
InventorFred J. Stevens
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Abstract
A novel method of electric field flow fractionation for separating solute molecules from a carrier solution is disclosed. The method of the invention utilizes an electric field that is periodically reversed in polarity, in a time-dependent, wave-like manner. The parameters of the waveform, including amplitude, frequency and wave shape may be varied to optimize separation of solute species. The waveform may further include discontinuities to enhance separation.
Claims17
A method of field flow fractionation for fractionating solute molecules from a solution, said method comprising the steps of:
- causing said solution to flow through a fractionating conduit, under conditions of laminar fluid flow, said fractionating conduit having an input end wherein said solution is introduced into said conduit and a discharge end wherein said solution and fractionated solute is removed from said conduit;
- applying an electric field across said flowing solution, between said input end and said discharge end of said conduit, said electric field having at least one vector component in a direction orthogonal to the direction of solution flow;
- and
- periodically reversing the polarity of said electric field while said solution flows through said conduit.
A method of fractionating a plurality of differing compositions of solute molecules from a solution, said differing compositions of solute molecules having differing electrophoretic mobilities in said solution, said method comprising the steps of:
- causing said solution to flow through a fractionating conduit, under conditions of laminar flow, said fractionating conduit having an input end wherein said solution is introduced into said conduit and a discharge end wherein said solution and fractionated composition of solute molecules are removed from said conduit, and said conduit defining an interior working chamber having a predetermined axial length between a pair of opposing conduit walls;
- applying an electric field of a predetermined amplitude, A, across said flowing solution in said interior working chamber, said electric field having at least one vector component orthogonal to the direction of laminar solution flow;
- and
- periodically reversing the polarity of said electric field as a function of time so that said differing compositions of solute molecules elute from said discharge end of said conduit at different times under said conditions of laminar flow.
Dependencies are inferred from the claim text.