Continuous steric FFF device for the size separation of particles

Abstract

A method and apparatus for continuous, steric field-flow fractionation and segregation of particles according to particle size. An elongate, fluid flow channel carrying a stream of entrained particles is subjected to a force field which urges the particles against one of the channel walls. The field strength is sufficient and in an appropriate direction to maintain the particles in close proximity to the wall so that particle size determines the rate of movement down the channel, the larger particles being exposed to the higher flow rates toward the center of the flow stream. The combined effects of fluid flow forces and force field strength develops a pattern of selective particle deflection from a point of particle infusion near the top of the channel, such that the particles drift and settle into segregated groups of common particle size. Where gravity is used as the force field, the desired particle movement is obtained by rotating the flow channel about an axis substantially parallel to the direction of flow to an inclined position with respect to the force field.

Dependencies are inferred from the claim text.