Patent ID: 7160735

Claim:
A composition comprising: a mixture of more than one microparticle, each microparticle having a surface with at least one first binding moiety and one or more molecular tags attached, each first binding moiety being specific for a member of a plurality of analytes and the one or more molecular tags being attached to the surface by cleavable linkages, such that different pairs of molecular tags and binding moieties are attached to different microparticles, the molecular tags being selected from a plurality of molecular tags such that each molecular tag of the plurality has one or more physical and/or optical characteristics distinct from those of the other molecular tags of the plurality so that each molecular tag forms a distinguishable peak upon cleavage and upon separation based on such one or more physical and/or optical characteristics; and at least one second binding moiety specific for at least one of said one or more target analytes, each second binding moiety having a sensitizer for generating an active species within an effective proximity, wherein at least one second binding moiety is specifically bound to a target analyte so that the cleavable linkage of a molecular tag of a first binding moiety specifically bound to the same target analyte is within the effective proximity of the sensitizer of the second binding moiety.