Application of inductively coupled plasma sector field mass spectrometry for low-level environmental americium-241 analysis

An improved and novel sample preparation method for ²⁴¹Am analysis by inductively coupled plasma sector field mass spectrometry has been developed. The procedure involves a selective CaF₂ pre-concentration followed by an extraction chromatographic separation using TRU™ resin. The achieved absolute detection limit of 0.86 fg (0.11 mBq) is comparable to that of alpha spectrometry (0.1 mBq) and suitable for low-level environmental measurements. Analysis of different kinds of environmental standard reference materials (IAEA-384 - Fangataufa lagoon sediment, IAEA-385 - Irish Sea sediment and IAEA-308 - Mixed seaweed from the Mediterranean Sea) and alpha spectrometry were used to validate the procedure. The chemical recovery of sample preparation ranged between 72 and 94%. The results obtained are in good agreement with reference values and those measured by alpha spectrometry. The proposed method offers a rapid and less labor-intensive possibility for environmental ²⁴¹Am analysis than the conventionally applied radioanalytical techniques.