RADIOACTIVELY LABELED SUBSTANCE

摘要

Disclosed are: a radioactively labeled substance which can be accumulated in a target efficiently and is highly stable in vivo; and diagnosis and treatment using the radioactively labeled substance. Specifically disclosed are: a radioactively labeled substance which comprises a complex composed of a ligand and a radioactive nuclear species of a metal (e.g., technetium, rhenium) and of which accumulation in a target site is increased, wherein the ligand is bound to a compound capable of binding to a target molecule and can form a polycoordinated complex with the metal; use of the radioactively labeled substance for diagnosis or treatment; a ligand for use in the preparation of the radioactively labeled substance; a kit comprising a material comprising the ligand and a material comprising a radioactive nuclear species of a metal, wherein both the materials are packed in separate package units; and a method for increasing the accumulation of a radioactively labeled substance in a target site, which is characterized by using the aforementioned radioactively labeled substance.