Sets of generalized target-binding e-tag probes

A set of electrophoretic tag (e-tag) probes for detecting the binding of or interaction between each or any of a plurality of ligands and one or more target antiligands, the set comprising j members, and each of said e-tag probes having the form:

• (D, Mj)-L-Tj, where
• (a) D is a detection group comprising a detectable label;
• (b) Tj is a ligand capable of binding to or interacting with a target antiligand,
• (c) L is a linking group connected to Tj by a bond that is cleavable by a selected cleaving agent when the probe is bound to or interacting with the target antiligand, wherein cleavage by said agent produces an e-tag reporter of the form (D, Mj)-L′, where L′ is the residue of L attached to (D, Mj) after such cleavage,
• (d) Mj is a mobility modifier having a charge/mass ratio that imparts a unique and known electrophoretic mobility to a corresponding e-tag reporter of the form (D, Mj)-L′, within a selected range of electrophoretic mobilities with respect to other e-tag reporters of the same form in the probe set;
• and
• (e) (D, Mj)-includes both D-Mj- and Mj-D-;
• said uncleaved or partially cleaved e-tag probes, but not the corresponding e-tag reporter, having one or more chemical groups capable of reacting with or binding to a selected capture agent that is effective to
• (i) impart a mobility to the probes bound to capture agent that prevents the probes from electrophoretically migrating within said range of electrophoretic mobilities or
• (ii) immobilize the probes on a solid support.