Patent ID: 7338762

Claim:
A method for isolation of a target comprising the steps of: dispersing one or more probe beads comprising a thioaptamer library selected from thioaptamers (S—ODN) or dithioaptamers (S 2 —ODN) in a thixotropic agent, wherein the thioaptamers comprises one or more but less than all of the linkages selected from the group rATP(αS 2 ), rUTP(αS 2 ), rGTP(αS 2 ), rCTP(αS 2 ), rATP(αS), dTTP(αS), dGTP(αS), dCTP(αS), dATP(αS 2 ), dTTP(αS 2 ), dGTP(αS 2 ) and dCTP(αS 2 ); scanning for probe beads that generate a detectable signal from interaction between the one or more probe beads and the target; and picking one or more probe beads based on the detectable signal; extracting the target from the probe bead; and identifying the target by mass spectrometry after liquid chromatography.