A process for the preparation and application of synthetic biotinylated peptides

The disclosure pertains to an immunoassay method using a detector substance which interacts with a substrate to be detected. The detector substance is a mixture of at least two different types of detector molecule; these detector molecules each carry at different positions a chemical group A which is capable of forming an affinity bond; the detector substance comprising at least two different types of detector molecule is brought into contact with a sample containing the substrate to be detected; once complexes are formed between the substrate and the two types of detector molecule, they are immobilised and/or detected with an affinity substance which forms an affinity bond with the chemical group A.