Radionuclides & Tracers at a Glance
Side-by-side comparison of the major radionuclides (emission, half-life, production) and radiopharmaceuticals (target, modality, use, and matched therapy)
Quick Answer
Two lookup tables for fast comparison. The first sorts the radionuclides by what they emit, how long they last, and how they are made, which is what determines whether an isotope images, treats, or both. The second sorts the radiopharmaceuticals by target, modality, and primary use, with the matched therapy for the theranostic pairs. For the interactive, filterable version organized by mechanism class, see the Radiopharmaceutical Compendium; for the decay math, the decay calculator.
Radionuclides at a glance
Half-life sets the logistics (generator, cyclotron, or reactor, and how far a dose can travel) and, with biological clearance, the dose delivered. Emission type sets the role: positrons annihilate to 511 keV pairs for PET; a single γ in the ~100–360 keV window images on a gamma camera; β⁻ and α deposit energy locally to treat.
| Radionuclide | Decay / main emission | Half-life | Production | Role |
|---|---|---|---|---|
| F-18 | β⁺ · 511 keV | 110 min | Cyclotron | PET workhorse (FDG, NaF, PSMA, FES) |
| Ga-68 | β⁺ · 511 keV | 68 min | Ge-68/Ga-68 generator | PET (DOTATATE, PSMA) |
| C-11 | β⁺ · 511 keV | 20 min | Cyclotron (on-site) | PET (choline, methionine) |
| N-13 | β⁺ · 511 keV | 10 min | Cyclotron (on-site) | PET (ammonia, myocardial perfusion) |
| O-15 | β⁺ · 511 keV | 2 min | Cyclotron (on-site) | PET (water perfusion; research) |
| Rb-82 | β⁺ · 511 keV | 75 s | Sr-82/Rb-82 generator | PET myocardial perfusion |
| Cu-64 | β⁺ / β⁻ / EC · 511 keV | 12.7 h | Cyclotron | PET (investigational; theranostic-capable) |
| Zr-89 | β⁺ · 511 keV | 78 h (3.3 d) | Cyclotron | Immuno-PET (antibody labelling) |
| Tc-99m | IT · γ 140 keV | 6.0 h | Mo-99/Tc-99m generator | SPECT workhorse (~most SPECT studies) |
| I-123 | EC · γ 159 keV | 13.2 h | Cyclotron | SPECT (thyroid, MIBG, DaTscan) |
| In-111 | EC · γ 171 / 245 keV | 2.8 d | Cyclotron | SPECT (octreotide, labelled WBC) |
| Ga-67 | EC · γ 93 / 185 / 300 keV | 3.3 d (78 h) | Cyclotron | SPECT (infection / inflammation) |
| Tl-201 | EC · Hg X-rays ~69–80 keV | 73 h | Cyclotron | SPECT (perfusion / viability; legacy) |
| I-131 | β⁻ (606 keV) · γ 364 keV | 8.0 d | Reactor | Therapy and imaging (thyroid, MIBG) |
| Lu-177 | β⁻ (~500 keV) · γ 113 / 208 keV | 6.65 d | Reactor | Therapy; imageable (DOTATATE, PSMA) |
| Y-90 | β⁻ (2.28 MeV) · pure β | 64 h (2.67 d) | Reactor / generator | Therapy (radioembolization, ibritumomab); no imaging γ |
| Ra-223 | α | 11.4 d | Decay of Ac-227 | Therapy (bone-dominant prostate) |
| Ac-225 | α (decay chain) | 10 d | Th-229 / accelerator | Therapy (PSMA; investigational) |
| Sm-153 | β⁻ · γ 103 keV | 46 h | Reactor | Bone-pain palliation (imageable) |
| Sr-89 | β⁻ · pure β | 50.5 d | Reactor | Bone-pain palliation |
| P-32 | β⁻ · pure β | 14.3 d | Reactor | Polycythemia vera, effusions (historical) |
Radiopharmaceuticals at a glance
Colour dots follow the atlas's consistent per-tracer colours. The matched therapy column names the therapeutic partner where the target is a theranostic pair.
| Tracer | Isotope | Half-life | Target / mechanism | Modality | Primary use | Matched therapy |
|---|---|---|---|---|---|---|
| FDG | F-18 | 110 min | Glucose metabolism (GLUT / hexokinase) | PET | Oncology staging & response, infection, viability, brain | — |
| PSMA (Ga-68 / F-18) | Ga-68 / F-18 | 68 / 110 min | PSMA (prostate) | PET | Prostate staging & recurrence; RLT selection | ¹⁷⁷Lu- / ²²⁵Ac-PSMA |
| DOTATATE | Ga-68 | 68 min | Somatostatin receptor 2 | PET | NET staging; PRRT selection | ¹⁷⁷Lu-DOTATATE |
| FDOPA | F-18 | 110 min | AADC / catecholamine pathway | PET | Parkinsonism, NET, glioma | — |
| FES | F-18 | 110 min | Estrogen receptor | PET | ER-positive breast cancer | (guides endocrine therapy) |
| Fluciclovine | F-18 | 110 min | Amino-acid transport | PET | Prostate biochemical recurrence | — |
| Choline | C-11 / F-18 | 20 / 110 min | Cell-membrane synthesis | PET | Prostate recurrence; parathyroid | — |
| Rubidium-82 | Rb-82 | 75 s | K⁺ analog (perfusion) | PET | Myocardial perfusion | — |
| N-13 ammonia | N-13 | 10 min | Perfusion | PET | Myocardial perfusion | — |
| Sestamibi | Tc-99m | 6 h | Mitochondrial / perfusion | SPECT | MPI; parathyroid | — |
| MDP / HDP | Tc-99m | 6 h | Hydroxyapatite | SPECT | Bone scan | — |
| NaF | F-18 | 110 min | Hydroxyapatite | PET | Bone (higher resolution) | — |
| MAG3 | Tc-99m | 6 h | Tubular secretion (ERPF) | SPECT | Renal function & drainage | — |
| DTPA | Tc-99m | 6 h | Glomerular filtration | SPECT | GFR, renography, aerosol ventilation | — |
| DMSA | Tc-99m | 6 h | Cortical tubular binding | SPECT | Renal cortex / scarring | — |
| MAA | Tc-99m | 6 h | Capillary micro-embolization | SPECT | Lung perfusion; Y-90 lung-shunt | — |
| Sulfur colloid | Tc-99m | 6 h | Phagocytosis (reticuloendothelial) | SPECT | Liver/spleen, lymphoscintigraphy, GI bleed, marrow | — |
| HIDA | Tc-99m | 6 h | Hepatocyte uptake & excretion | SPECT | Hepatobiliary (acute cholecystitis, leak) | — |
| PYP | Tc-99m | 6 h | ATTR amyloid binding | Planar / SPECT | Cardiac ATTR amyloidosis | — |
| Pertechnetate | Tc-99m | 6 h | NIS trapping (not organified) | SPECT | Thyroid, Meckel, salivary | — |
| Radioiodine | I-123 / I-131 | 13 h / 8 d | NIS (trap & organify) | SPECT / planar | Thyroid uptake & scan; I-131 therapy | ¹³¹I |
| MIBG | I-123 / I-131 | 13 h / 8 d | Norepinephrine transporter | SPECT | Pheo/paraganglioma, neuroblastoma | ¹³¹I-MIBG |
| Ioflupane (DaTscan) | I-123 | 13 h | Dopamine transporter (DAT) | SPECT | Parkinsonian syndromes vs essential tremor / DLB | — |
| Gallium-67 | Ga-67 | 78 h | Transferrin / lactoferrin | SPECT | Infection / inflammation (niche) | — |
| Thallium-201 | Tl-201 | 73 h | K⁺ analog | SPECT | Perfusion / viability (legacy) | — |
| FAPI | Ga-68 / F-18 | 68 / 110 min | Fibroblast activation protein | PET | Pan-cancer stroma (investigational) | (FAP-targeted, investigational) |
How to read these
Emission determines role: positron emitters (F-18, Ga-68, Rb-82) are for PET; single-γ emitters in the ~100–360 keV window (Tc-99m, I-123, In-111) are for SPECT; β⁻ and α emitters (Lu-177, Y-90, I-131, Ra-223, Ac-225) deposit energy locally to treat. Half-life determines whether a nuclide is made on-site (C-11, N-13, O-15, Rb-82), shipped from a regional cyclotron (F-18), eluted from a generator at the point of care (Tc-99m, Ga-68, Rb-82), or reactor-produced for therapy (I-131, Lu-177, Y-90). The theranostic pairs share a target across the two tables: image with the diagnostic isotope, treat with the therapeutic one on the same targeting molecule.
Self-Check
Q1. Which three radionuclides here are supplied by a generator at the point of care, and why does that matter?
Answer: Tc-99m (Mo-99/Tc-99m), Ga-68 (Ge-68/Ga-68), and Rb-82 (Sr-82/Rb-82). A generator lets a site produce a short-lived daughter on demand without an on-site cyclotron or same-day delivery — which is why Tc-99m dominates SPECT and Rb-82 enables PET perfusion without a cyclotron.
Q2. Why can Y-90 not be imaged the way Lu-177 and I-131 can?
Answer: Y-90 is essentially a pure β⁻ emitter with no imaging γ, whereas Lu-177 and I-131 emit imageable γ photons (permitting post-therapy SPECT). Y-90 distribution is inferred indirectly from bremsstrahlung SPECT or the small internal-pair-production PET signal.
Q3. Name the imaging isotope, therapy isotope, and shared target for the two flagship theranostic pairs.
Answer: Prostate/PSMA — image with Ga-68/F-18-PSMA, treat with ¹⁷⁷Lu-PSMA-617, target PSMA. NET/SSTR — image with ⁶⁸Ga-DOTATATE, treat with ¹⁷⁷Lu-DOTATATE, target somatostatin receptor 2.
Related Pages
- Radiopharmaceutical Compendium — the interactive, filterable version organized by mechanism class.
- Physics & Radiobiology — decay, emissions, and half-life in depth.
- Decay calculator — activity remaining after a given time.
Evidence & sources
https://nuc.med/radionuclides-tracers-comparison/ Report an issue