# Scandium-44

Source: https://nuclide.cc/isotopes/sc-44/  
Nuclide record `sc-44` (Isotope). Data CC BY-NC 4.0, attribute "Data from Nuclide (nuclide.cc)"; commercial use needs a licence.

## TL;DR

An experimental radioactive metal, lasting about four hours, being developed as a PET-imageable stand-in for lutetium-177 or other therapy metals so a treatment dose can be planned in advance.

## Summary

Scandium-44 decays with a 3.97-hour half-life and an unusually high positron branching ratio of about 94%, giving PET image quality that compares favourably with gallium-68 while lasting roughly three times as long, long enough for regional distribution from a centralised production site rather than only local cyclotron use. Its chemistry closely resembles that of lutetium-177 and other trivalent lanthanide-like therapy metals, so DOTA-chelated scandium-44 tracers have been explored as a pre-therapy dosimetry match for 177Lu-labelled radioligands such as PSMA-617, an alternative to using 68Ga for the diagnostic scan when a metal-matched surrogate is preferred.

It is produced on a medical cyclotron via 44Ca(p,n)44Sc on an enriched calcium-44 target (natural abundance only about 2%, so enrichment adds cost), or via a 44Ti/44Sc generator in which the long-lived (60.4-year) parent titanium-44 supplies scandium-44 on an ongoing basis without a cyclotron, analogous to a 68Ge/68Ga generator.

Scandium-44 is also discussed as the diagnostic half of a prospective 44Sc/47Sc theranostic pair, since 44Sc and the beta-emitting therapy isotope scandium-47 are chemically identical, but as of the mid-2020s this pairing remains in early clinical and preclinical research rather than routine practice, and 47Sc production has not yet reached clinical scale.

## Fields

- Kind: Isotope
- Status: preclinical
- Last checked: 2026-09-22
- Also known as: 44Sc
- Tags: positron emitter; generator; experimental theranostic pair

## Sources

- PMC: production of scandium radionuclides for theranostic applications: https://pmc.ncbi.nlm.nih.gov/articles/PMC8149571/
- PMC: current state of 44Ti/44Sc radionuclide generator systems: https://pmc.ncbi.nlm.nih.gov/articles/PMC10375575/

## Connected records

- technologies: [Cyclotron isotope production (F-18, Ga-68, Cu-64, Zr-89, At-211)](https://nuclide.cc/technologies/cyclotron-isotope-production/), [PET (positron emission tomography)](https://nuclide.cc/technologies/pet/), [Radioligand dosimetry](https://nuclide.cc/technologies/radioligand-dosimetry/)
- ideas: [Total-body PET for personalised radioligand dosing](https://nuclide.cc/ideas/idea-total-body-pet-dosimetry/)
- terms: [Chelator (bifunctional chelating agent)](https://nuclide.cc/terms/chelator-term/), [Theranostic pair](https://nuclide.cc/terms/theranostic-pair-term/)

---
JSON: https://nuclide.cc/api/v1/entities/sc-44.json