Development of Tritium AMS for Biomedical Sciences Research

Abstract

Tritium ({sup 3}H) is a radioisotope that is extensively utilized in biological research. Normally in the biological sciences, {sup 3}H is quantified by liquid scintillation counting. For the most sensitive measurements, liquid scintillation counting requires large samples and counting times of several-hours. In contrast, provisional studies at LLNL's Center for Accelerator Mass Spectrometry have demonstrated that Accelerator Mass Spectrometry (AMS) can be-used to quantify {sup 3}H in milligram-sized biological samples with a 100 1000-fold improvement in detection limits when compared to scintillation counting. This increased sensitivity is expected to have great impact in the biological research community. However, before {sup 3}H AMS can be used routinely and successfully, two areas of concern needed to be addressed: (1) sample preparation methods needed to be refined and standardized, and (2) smaller and simpler AMS instrumentation needed to be developed. To address these concerns, the specific aims of this project were to: (1) characterize small dedicated {sup 3}H AMS spectrometer (2) develop routine and robust biological sample preparation methods, and (3) with the aid of our external collaborations, demonstrate the application of {sup 3}H AMS in the biomedical sciences. Towards these goals, the {sup 3}H AMS instrument was installed and optimized to enhancemore » performance. The sample preparation methodology was established for standard materials (water and tributyrin) and biological samples. A number of biological and environmental studies which require {sup 3}H AMS were undertaken with university collaborators and our optimized analysis methods were employed to measure samples from these projects.« less