Radioisotope gallium-labelled radiopharmaceuticals have been applied in nuclear medical diagnosis, e.g., .sup.67 Ga-citrate for tumor and abscess imaging, .sup.68 Ga-EDTA for detection of blood-brain barrier defect, .sup.68 Ga-tripolyphosphate for bone scanning, .sup.67 Ga-dimethylgallium (III) acetylacetonate for heart imaging. There are two gallium radioisotopes which are labelled radiopharmaceuticals. One is gallium-67 which is cyclotron produced by .sup.68 Zn(P,2n).sup.67 Ga. The physical half-life of .sup.67 Ga is 3.3 days. Ga-67 radiopharmaceuticals have played a major role in diagnostic imaging using Single Photon Emission Computed Tomography (SPECT). The other is gallium-68 which is .sup.68 Ge/.sup.68 Ga generator-produced positron-emitting radionuclides. The physical half-life of the parent, .sup.68 Ge, is 275 days. The physical half-life of the daughter, .sup.68 Ga, is 68 min, which is labelled radiopharmaceuticals for positron emission tomography (PET). Today, the clinical application of gallium radiopharmaceuticals is the use of gallium-67 citrate for tumor and abscess imaging. The gallium-68 will dominate a role in the future, as PET imaging centers become more available.
USPTO Backgrounds
USPTO Backgrounds