{"entity":{"id":"y-86","kind":"isotope","name":"Yttrium-86","aka":["86Y"],"tldr":"A PET-visible radioactive stand-in for the treatment isotope yttrium-90, used to see in advance, on a scan, exactly where a yttrium-90 therapy dose would go and how much radiation each organ would receive.","summary":"Yttrium-90, used for radioembolisation (TARE/SIRT) and older radioimmunotherapy agents, is a pure beta emitter with no directly imageable gamma or positron emission, which makes patient-specific pre-therapy dosimetry difficult. Yttrium-86 solves that problem: it is chemically identical to yttrium-90, so an 86Y-labelled version of the same antibody, peptide or microsphere construct has an identical biodistribution, and its 14.7-hour half-life with about 33% positron emission allows PET imaging over two to three days, long enough to build a full time-activity curve and calculate the organ and tumour doses a subsequent 90Y therapy would deliver.\n\nIt is produced on a cyclotron via 86Sr(p,n)86Y on an enriched strontium-86 target (typically SrCO3 or SrO), the preferred route because it gives the highest radionuclidic purity; the main radionuclidic impurity, 87mY, is normally kept below a few percent when highly enriched target material is used. Bombardments of a few hours at modest beam currents (2-6 microamps) are typical.\n\nThe approach was first used clinically at Forschungszentrum Jülich for pre-therapy dosimetry ahead of 90Y-citrate treatment of bone metastases, and has since been applied to 86Y-DOTA-peptide imaging ahead of 90Y-labelled somatostatin analogue therapy; it remains a research and specialist-dosimetry tool rather than a routinely stocked clinical isotope, since both the cyclotron target and the imaging protocol are non-standard.","status":"preclinical","asOf":"2026-09-22","links":[{"label":"PMC: 86Y-based PET radiopharmaceuticals, radiochemistry and applications","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC3184346/"},{"label":"DOE Isotope Program (NIDC): yttrium-86 availability","url":"https://www.isotopes.gov/node/215"}],"tags":["positron emitter","dosimetry surrogate","theranostic pair"],"related":[],"indications":[],"sections":[],"technologies":["pet","radioligand-dosimetry","cyclotron-isotope-production"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"symbol":"86Y","element":"Yttrium","massNumber":86,"halfLife":"14.7 hours","emissions":["β+ ~33% (max 3.15 MeV)","electron capture ~67%","multiple γ (443-1921 keV)"],"emissionClass":"positron","use":"imaging","production":"Cyclotron: 86Sr(p,n)86Y on enriched strontium-86 target (SrCO3 or SrO), typically 2-6 microamp beam current for under 4 hours.","supply":"research-only","supplyNote":"Made at a small number of research cyclotrons (including the US DOE Isotope Program's Brookhaven Linac Isotope Producer, available on an as-needed basis) with enriched 86Sr targets; used for dosimetry research rather than stocked as a routine clinical isotope.","chelators":["DOTA"],"pairedWith":["y-90"],"since":1993},"route":"/isotopes/y-86/","neighbours":{"technology":[{"id":"albumin-binder-ligands","kind":"technology","name":"Albumin-binder ligands","route":"/technologies/albumin-binder-ligands/"},{"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":"pet","kind":"technology","name":"PET (positron emission tomography)","route":"/technologies/pet/"},{"id":"radioligand-dosimetry","kind":"technology","name":"Radioligand dosimetry","route":"/technologies/radioligand-dosimetry/"}],"term":[{"id":"chelator-term","kind":"term","name":"Chelator (bifunctional chelating agent)","route":"/terms/chelator-term/"},{"id":"theranostic-pair-term","kind":"term","name":"Theranostic pair","route":"/terms/theranostic-pair-term/"}]}}