Patent ID: 8360244
Filing Date: 2013-01-29
Classification: G01N,Y10T

Abstract:
1. A method to improve the characterization of particles separated by an asymmetric flow field flow fractionation unit, A4F, whose structure comprises i. a top plate assembly containing ports, ii. a spacer containing two or more cavities separating said top plate assembly from a bottom plate assembly, iii. a membrane preventing particles from entering iv. a supporting fit structure, and v. a bottom plate assembly to which said top plate assembly can be rigidly attached sealing, thereby, said cavity between said membrane and said top plate; comprising the steps of A. assembling a channel structure which provides a plurality of cavities of different cavity configurations by using one spacer containing a plurality of cavities of different cavity configurations therein; B. creating a suspension of said particles to be characterized; C. injecting an aliquot of said particles into a first cavity configuration of said A4F channel means; D. fractionating said injected aliquot by said first cavity configuration; E. measuring said fractionated aliquot by detector means; F. injecting successively a plurality of aliquots of said particles into said corresponding plurality of additional cavity configurations within said same channel structure without the need to disassemble said channel structure; G. fractionating successively each said injected aliquot by means of said corresponding subsequent cavity configuration selected; H. measuring successively said fractionated aliquots of said particles by said detector means; and I. combining all such measurements collected from all aliquots so measured to provide improved characterization of said particles.