Synthesis of new head-activator analogues and their application for improved radioimmunoassays

New analogues of head activator were produced for receptor and radioimmunoassay studies. The precursor molecules [(4'-I)Phe11] head activator and [Tyr11] head activator were synthesised for catalytic tritiation and iodination, respectively. With the tracer [(3,5-125 I2)Tyr11] head activator the sensitivity range of the radioimmunoassay was 5-100 fmol.