Automated flow electrolysis coupled with solid-phase extraction and ICP-MS/MS for rapid determination of neptunium-237

柳澤 華代   ; 松枝 誠   ; 岡 壽崇   ; 北辻 章浩  

Yanagisawa, Kayo; Matsueda, Makoto; Oka, Toshitaka; Kitatsuji, Yoshihiro

Conventional methods for determining neptunium-237 are labor-intensive and time-consuming, involving manual valence adjustments followed by chemical separation. These procedures are typically performed in open systems, which increases the risks of contamination, sample loss, and radiation exposure to workers. We developed a fully automated, semi-closed system that integrates flow electrolysis with solid-phase extraction and inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) to address these limitations. The system achieved a detection limit of 3.6 mBq/L (approximately 0.14 ng/L) with a 1 mL sample injection and a total analysis time of 25 min, enabling high-throughput analysis. Recovery tests using steel waste samples showed good agreement with the spiked values.