Patent ID: 7897348

Claim:
A method for purifying a negatively charged analyte from a first aqueous solution, comprising (a) immobilizing a cationic polymer on a solid support, wherein said cationic polymer has the following general formula: wherein: i) m is an integer ranging for 2 to 3; ii) n is an integer ranging from 3 to 100; iii) R* is a quaternary ammonium; iv) Y is an oxygen atom or a methylene; and v) R 1 is a methyl group or a hydrogen atom; (b) contacting the immobilized polymer with the first aqueous solution, wherein the first aqueous solution favors electrostatic interactions between the negatively charged analyte and the cationic polymer to create an analyte/cationic polymer complex, thereby capturing the negatively charged analyte on said solid support; (c) disrupting the analyte/cationic polymer complex by contacting the complex with an elution solution to release the analyte, wherein the elution disrupts the electrostatic interactions between the negatively charged analyte and the cationic polymer; and (d) purifying the released analyte.