Gallium-68 (Ga-68) is a radioactive isotope of gallium with a half-life of approximately 68 minutes. It decays by positron emission (beta-plus decay) to stable zinc-68 (Zn-68), making it a valuable isotope for positron emission tomography (PET) imaging. Ga-68 is typically obtained from a germanium-68/gallium-68 generator, where it is produced as a decay product of germanium-68.

Gallium emits an annihilation line similar to Fluorine-18. These two isotopes can only be distinguished by evaluating their half-lives: Fluorine-18 has a half-life of 109 minutes, compared to 68 minutes for Gallium.

Ga-68 is widely used in nuclear medicine, particularly in PET imaging. It is a key isotope in radiopharmaceuticals for diagnosing cancer and other diseases. Ga-68-labeled compounds, such as Ga-68 DOTATATE and Ga-68 PSMA, are used for imaging neuroendocrine tumors and prostate cancer, respectively. These radiopharmaceuticals target specific receptors or antigens, enabling high-resolution imaging to detect and stage diseases with great accuracy. The short half-life of Ga-68 allows for rapid imaging while minimizing radiation exposure to the patient.

Ga-68 is not naturally occurring and is produced artificially. It is typically extracted from germanium-68/gallium-68 generators, which are used in hospitals and medical facilities. These generators provide a reliable on-site source of Ga-68 for radiopharmaceutical preparation. Due to its short half-life, Ga-68 is encountered only in controlled medical and research environments, and its production and use are strictly regulated to ensure safety and efficacy in clinical applications.