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Isotope Sciences Program


Gadolinium-153 is a low-energy gamma-emitter with an 8-month half-life. It is used in many quality assurance applications, such as line sources and calibration phantoms, to ensure that nuclear medicine imaging systems operate correctly and produce useful images of radioisotope distribution inside the patient. Gadolinium-153 is not used internally.

Gadolinium-153 is produced in a nuclear reactor from elemental europium or enriched gadolinium targets. Using hot-cell methods, we process europium oxide targets from the Advanced Test Reactor at Idaho National Laboratory. We extract and purify the gadolinium-153 product, separating it from europium radioactive waste.

The recovery of high-purity gadolinium-153 from reactor targets represents a complex and challenging task for radiochemists. New radiochemical separations methods developed at Pacific Northwest National Laboratory improve the gadolinium-153 purity, reduce flammability hazards in the hot cell, and reduce the overall cost of radiochemical separations.

Gadolinium-153 helps calibrate single photon-emission computed tomography (SPECT) systems that are used in nuclear medicine for functional imaging. In these brain images from an epilepsy patient, we compare SPECT images (middle and right) to magnetic resonance imaging (left). The SPECT images provide functional information about patient health, whereas the MRI image provides only anatomical detail.

Isotope Sciences Program

Medical Isotopes