Patent ID: 6902889
Filing Date: 2005-06-07
Classification: G01N

Abstract:
1. An ion-exchange chromatographic assay method, comprising the steps of: a) providing a polymeric membrane type flow matrix attached to a liquid-impervious backing, which flow matrix permits a capillary force assisted lateral flow therethrough, and at least a part of which flow matrix contains ion-exchange functional groups selected from the group consisting of diethyl aminoethyl (DEAE), trimethyl hydroxypropyl (QA), quaternary aminoethyl (QAE), quaternary aminomethyl (Q), diethyl-(2-hydroxypropyl)-aminoethyl, triethyl aminomethyl (TEAE), triethylaminopropyl (TEAP), polyethyleneimine (PEI), methacrylate, carboxymethyl (CM), orthophosphate (P), sulfonate (S), sulfoethyl (SE) and sulfopropyl (SP), wherein the flow matrix is a porous polymer material with pores in the range of 0.01-20 μm; b) treating the flow matrix to reduce or eliminate nonspecific adsorption properties of the flow matrix; c) applying to the flow matrix a sample containing at least two components; d) initiating a first lateral flow of aqueous fluid to transport the sample through the flow matrix and chromatographically separate each of the two components from one another and from the sample as they flow along the lateral flow matrix; e) interrupting said lateral flow; and either f1) detecting at least one of said separated components on the flow matrix in the position reached by the respective component when the flow was interrupted; or f2a) initiating a second flow of aqueous fluid to transport the components in a direction substantially transverse to the direction of the first lateral flow, f2b) interrupting said second lateral flow; and f2c) detecting at least one of said separated components on the flow matrix in the position reached by the respective components when the second lateral flow was interrupted.