Kits employing generalized target-binding e-tag probes

A kit of specific binding pairs for detecting the presence or absence of one or more target compounds, the kit comprising a plurality of pairs of first reagents and second reagents, the first reagent and second reagent of each pair binding to the same target compound, the first reagent of each pair being selected from the group defined by the formula:

• [(D, M)—L]k—T
• wherein:
• T is a target-binding moiety specific for a target compound,
• k is an integer in the range of from 1 to 20,
• L is a cleavable linkage,
• D is a detection group, and
• M is a mobility modifier consisting of from 1 to 500 atoms selected from the group consisting of carbon, hydrogen, oxygen, sulfur, nitrogen, phosphorus, and boron, wherein upon cleavage of L an eTag reporter comprising a detection group, D, and a mobility modifier, M, is produced with a distinct charge/mass ratio so that eTag reporters of different electrophoretic probes form distinct peaks upon electrophoretic separation;
• and
• the second reagent of each pair being capable of generating an active species to cleave cleavable linkages of first reagents that bind to the same target compound as said second reagent, the active species being selected from the group consisting of singlet oxygen, hydrogen peroxide, NADH, and hydrogen radicals.