Assay method utilizing photoactivated chemiluminescent label

A method for determining an analyte, said method comprising:

• combining in an assay medium (1) a medium suspected of containing an analyte, and (2) a label reagent comprising a member of a specific binding pair (sbp member) bound to a photochemically activatable chemiluminescent compound (PACC) under conditions wherein an sbp member complex involving said label reagent is formed in relation to the presence of analyte in said medium,
• irradiating said assay medium with light to activate said PACC, and
• examining said assay medium for a signal, the presence or intensity thereof being related to the amount of analyte in said medium.

A method for determining an analyte, said method comprising:

• combining in an assay medium either simultaneously or wholly or partially sequentially (1) a medium suspected of containing an analyte, (2) a label reagent comprising a first member of a specific binding pair (sbp member) bound to a compound capable of chemiluminescence upon reaction with singlet oxygen ("said compound"), (3) a singlet oxygen generator, and (4) a reagent comprising a fluorescent energy acceptor bound to, or capable of becoming bound to, a second sbp member, under conditions wherein an sbp member complex involving said label reagent and said energy acceptor is formed in relation to the presence of analyte in said medium and energy from said compound is capable of activating said fluorescent energy acceptor,
• activating said singlet oxygen generator, and
• examining said assay medium for a signal, the presence or intensity thereof being related to the amount of analyte in said medium.

A method for determining a polynucleotide analyte, said method comprising:

• combining in an assay medium, (1) a sample suspected of containing a polynucleotide analyte and (2) a label reagent comprising a photochemically activatable chemiluminescent compound (PACC) bound to a polynucleotide, at least a portion of which is capable of hybridizing with said polynucleotide analyte, under conditions wherein said label reagent hybridizes with said polynucleotide analyte if present,
• irradiating said assay medium to activate said PACC, and
• measuring the fluorescent energy emitted from said medium, the amount thereof being related to the amount of analyte in said sample.

A composition comprising a photochemically activated chemiluminescent compound (PACC) associated with a member of a specific binding pair.

A kit comprising in packaged combination:

• (1) a composition comprising a photochemically activatable chemiluminescent compound (PACC), having bound thereto a specific binding pair (sbp) member, and (2) a photosensitizer which is not in said composition.