A homogeneous assay for determining analyte

摘要

Methods are disclosed for determining an analyte in a medium suspected of containing the analyte. One method comprises providing in combination (1) a medium suspected of containing an analyte; (2) a label reagent comprising a suspendible particle and a first specific binding pair (sbp) member associated with a photochemically activatable chemiluminescent compound (PACC), wherein said first sbp member is capable of binding to said analyte or to a second sbp member, wherein said second sbp member is capable of binding to said analyte; and (3) an intrinsically metastable species capable of diffusing in said medium and of reacting preferentially with said PACC when said PACC is brought into close proximity to said species by virtue of the presence or absence of said analyte; and determining whether said intrinsically metastable species has reacted with said PACC, the reaction thereof being related to the amount of analyte in said medium.