文摘
151Sm is an interesting nuclide in many research fields. Measurement methods of the long-lived 151Sm with accelerator mass spectrometry have been developed at China Institute of Atomic Energy. The chemical form of samples was Sm2O3 and the extracted ion was SmO−. To date, the sensitivity, that is, the isotopic ratio, of 151Sm measured using accelerator mass spectrometry is about 10−8. This method was also used to measure the concentration of tracer 151Sm in biological samples for clarifying whether the rare earth elements can enter into the brain. It is not possible at present to determine whether the tracer has penetrated the blood–brain barrier into the brain.