Patent ID: 6881589

Claim:
An electrochemiluminescent composition suitable for use in an electrochemiluminescent assay for an analyte of interest, comprising: (a) an electrochemiluminescent label; (b) a first binding reagent comprising a binding partner of (i) said analyte of interest, (ii) an analog of said analyte of interest, (iii) a binding partner of said analyte of interest, or (iv) a binding partner of said analog of said analyte of interest, wherein said first binding reagent is also a binding partner of or linked to said label; (c) collectable magnetic particles; (d) a second binding reagent comprising a binding partner of (i) said analyte of interest, (ii) an analog of said analyte of interest, (iii) a binding partner of said analyte of interest, or (iv) a binding partner of said analog of said analyte of interest wherein said second binding reagent is also a binding partner of or linked to said particles; and (e) an electrolyte wherein said composition is suitable for use in said assay for said analyte of interest.