Abstract text

An object of the present invention is to provide a method for detecting a protein using a nonradioactive label which is prevented to a smaller extent than in the case of the interaction of biotin/(strepto)avidin, and which achieves higher detection sensitivity than that of the detection system using DIG. The present invention provides a method for detecting a target substance, which comprises steps of: (A) allowing a target substance to come into contact with a protein labeled with a compound having a 6-membered ring, so as to carry out a binding reaction; and (B) detecting the protein labeled with the compound having a 6-membered ring, which was bound to the target substance, by using an antibody against the above compound having a 6-membered ring.