T01_P01

Double Trap Interface: A novel gas handling system for high throughput AMS analysis

De Maria D¹,  Fahrni S², Wacker L¹, Synal H¹

¹ETH Zurich, Zurich, Switzerland, ²Ionplus AG, Dietikon, Switzerland

Over the last decade, the interest in a combustion based AMS technology has increased due to significant progresses made towards compact AMS systems and the development of hybrid ion sources, allowing the analysis of samples in gaseous form.

To address the requirements of higher samples throughput and level of automation, a novel gas handling system, the Double Trap Interface (DTI), was developed. The instrument couples an elemental analyzer (EA) to the ion source of a MICADAS (Micro Carbon Dating System) AMS system. The DTI features two external traps filled with a zeolite molecular sieve, which collect the sample material in form of CO₂ after combustion with EA. Subsequently, the gaseous sample is released by thermal desorption and injected into the ion source. The alternating use of the traps allows a quasi continuous analysis, as the loading and measurement procedures are now decoupled and run in parallel on the two traps. The analysis of a sample requires less than 5 minutes, corresponding to a throughput of 12 to 13 samples per hour. To speed up further the measurement routine, we implemented an option allowing multiple analyses on a single cathode.

The main target are biomedical companies conducting metabolism and pharmacokinetic studies using radiocarbon as tracer during the validation of new pharmaceutical compounds. However, the EA-DTI system is not limited to biomedical studies only. The methodology has a huge potential for all applications requiring an increased throughput but less precision, as for example environmental tracer studies or the analysis of organic sediments.