Lawrence Livermore National Laboratory, University of California, Livermore, CA 94551, USA. jsvogel@llnl.gov
Accelerator mass spectrometry (AMS) counts individual rare, usually radio-, isotopes such as radiocarbon at high efficiency and specificity in milligram-sized samples. AMS traces very low chemical doses (micrograms) and radiative doses (100 Bq) of isotope-labeled compounds in animal models and directly in humans for pharmaceutical, nutritional, or toxicological research. Absorption, metabolism, distribution, binding, and elimination are all quantifiable with high precision after appropriate sample definition.