{"entity":{"id":"ge-68","kind":"isotope","name":"Germanium-68","aka":["68Ge","Ge-68"],"tldr":"The long-lived parent locked inside a gallium-68 generator. One loaded column can supply a year's worth of PET tracer doses for prostate cancer and neuroendocrine tumour scans, but the generators themselves have been expensive and slow to get.","summary":"Germanium-68 decays by electron capture with a 270.8-day (about 9-month) half-life, far too long to be imaged usefully itself; its entire clinical role is as the parent bound inside a 68Ge/68Ga generator column, decaying continuously to the 68-minute daughter gallium-68 that is eluted with dilute acid for use in PET tracers such as 68Ga-DOTATATE and 68Ga-PSMA-11. Because the parent's half-life is roughly 5,800 times the daughter's, a single generator loaded with germanium-68 supplies a fairly constant, though slowly declining, stream of gallium-68 for around a year before it needs replacing.\n\nGermanium-68 itself is made almost exclusively by high-energy proton bombardment of a gallium metal target enriched in the stable isotope gallium-69, via the 69Ga(p,2n)68Ge reaction; because commercial-scale generator loadings require tens of gigabecquerels of activity and the reaction needs proton energies of roughly 20-30 MeV over several days of irradiation at high beam current, only a small number of high-energy cyclotron and accelerator facilities worldwide can produce it (an alternative 66Zn(alpha,2n)68Ge route using alpha-particle beams exists but is less commonly used).\n\nThat narrow production base is why 68Ge/68Ga generator supply has repeatedly lagged clinical demand: GMP-grade generator lead times ran as long as 18 months in the years before the 2016-2020 approvals of gallium-68 DOTATATE and PSMA-11 PET agents, and a 2017 shortage of germanium feedstock further squeezed availability, prompting the IAEA in 2019-2020 to promote direct cyclotron production of gallium-68 (68Zn(p,n)68Ga) as a way to sidestep the germanium-68 bottleneck altogether rather than solve it. Manufacturers including Eckert & Ziegler subsequently expanded generator manufacturing capacity, and by the mid-2020s most large PET centres have access to either generator- or cyclotron-produced gallium-68, though the underlying germanium-68 production base remains concentrated in a handful of accelerator facilities.","status":"established","asOf":"2026-09-22","links":[{"label":"PMC: good practices for 68Ga radiopharmaceutical production (68Ge production section)","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC9588110/"},{"label":"Wikipedia: gallium-68 generator (68Ge production routes)","url":"https://en.wikipedia.org/wiki/Gallium-68_generator"},{"label":"IAEA: new CRP on cyclotron-based gallium-68 (2020)","url":"https://www.iaea.org/newscenter/news/new-crp-production-of-cyclotron-based-gallium-68-radioisotope-and-related-radiopharmaceuticals-f22073"}],"tags":["generator parent","long-lived","supply bottleneck"],"related":["ga-68","ga68-dotatate","ga68-psma-11"],"indications":[],"sections":[],"technologies":["radionuclide-generators-kits","sstr-pet","psma-pet","cyclotron-isotope-production"],"targets":[],"drugs":[],"companies":["eckert-ziegler","ire","isotopia"],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"symbol":"68Ge","element":"Germanium","massNumber":68,"halfLife":"270.8 days","emissions":["electron capture (decays to 68Ga)"],"emissionClass":"gamma","use":"imaging","production":"Cyclotron: 69Ga(p,2n)68Ge on gallium metal target enriched in gallium-69, requiring proton energies of roughly 20-30 MeV and multi-day, high-current irradiation; alternative 66Zn(alpha,2n)68Ge route with alpha-particle beams.","supply":"tight","supplyNote":"Production is concentrated at a small number of high-energy accelerator facilities because commercial generator loadings need irradiations of tens of thousands of microamp-hours; GMP generator lead times reached about 18 months before the PSMA PET launch, and a 2017 germanium feedstock shortage further tightened supply. IAEA-promoted direct cyclotron production of gallium-68 bypasses this bottleneck rather than resolving it.","chelators":[],"pairedWith":["ga-68"],"since":1960},"route":"/isotopes/ge-68/","neighbours":{"isotope":[{"id":"ga-68","kind":"isotope","name":"Gallium-68","route":"/isotopes/ga-68/"}],"drug":[{"id":"ga68-dotatate","kind":"drug","name":"Gallium-68 DOTATATE (and Cu-64 DOTATATE)","route":"/drugs/ga68-dotatate/"},{"id":"ga68-psma-11","kind":"drug","name":"Gallium-68 gozetotide (PSMA-11)","route":"/drugs/ga68-psma-11/"}],"technology":[{"id":"cold-kit-formulation","kind":"technology","name":"Cold kit formulation","route":"/technologies/cold-kit-formulation/"},{"id":"cyclotron-isotope-production","kind":"technology","name":"Cyclotron isotope production (F-18, Ga-68, Cu-64, Zr-89, At-211)","route":"/technologies/cyclotron-isotope-production/"},{"id":"ge68-ga68-generators","kind":"technology","name":"Germanium-68/gallium-68 generators","route":"/technologies/ge68-ga68-generators/"},{"id":"psma-pet","kind":"technology","name":"PSMA PET","route":"/technologies/psma-pet/"},{"id":"radionuclide-generators-kits","kind":"technology","name":"Radionuclide generators and cold kits","route":"/technologies/radionuclide-generators-kits/"},{"id":"sstr-pet","kind":"technology","name":"Somatostatin receptor PET (68Ga/64Cu-DOTATATE)","route":"/technologies/sstr-pet/"}],"company":[{"id":"bwxt-medical","kind":"company","name":"BWXT Medical","route":"/companies/bwxt-medical/"},{"id":"china-isotope-radiation","kind":"company","name":"China Isotope & Radiation Corporation","route":"/companies/china-isotope-radiation/"},{"id":"eckert-ziegler","kind":"company","name":"Eckert & Ziegler","route":"/companies/eckert-ziegler/"},{"id":"hta-atom-hi-tech","kind":"company","name":"HTA (Atom Hi-Tech)","route":"/companies/hta-atom-hi-tech/"},{"id":"ire","kind":"company","name":"IRE (Institut national des Radioéléments)","route":"/companies/ire/"},{"id":"isotopia","kind":"company","name":"Isotopia Molecular Imaging","route":"/companies/isotopia/"}]}}