Method and kit for detecting, or determining the quantity of, metabolites of fentanyl, and metabolites of fentanyl analogs.

摘要

An immunogen of the formula wherein Z1 is hydrogen and Z4 is selected from a coupled crosslinker to a carrier material conferring antigenicity or wherein Z2 is a coupled cross-linker to a carrier material conferring antigenicity in a position ortho, meta or para with the proviso that the immunogen is not a heterodimer of the formula: (BKAn) (X) (Y); where BKAn is a bradykinin antagonist peptide; wherein Y is: wherein R1 is the linking group X of the formula CH2CH2 (Phe) CH2C (O).