Development of rapid and sensitive bioassay methods to contribute to actinide internal exposure medical response

2022 Fiscal Year Research-status Report

• Project/Area Number: 22K12384
• Research Institution: National Institutes for Quantum Science and Technology
• Principal Investigator: 楊 国勝 国立研究開発法人量子科学技術研究開発機構, 放射線医学研究所 計測・線量評価部, 主任研究員 (10801227)
• Co-Investigator(Kenkyū-buntansha): 金 ウンジュ 国立研究開発法人量子科学技術研究開発機構, 放射線医学研究所 計測・線量評価部, 主幹研究員 (10370876) ; 鄭 建 国立研究開発法人量子科学技術研究開発機構, 放射線医学研究所 福島再生支援研究部, 上席研究員 (30370878)
• Project Period (FY): 2022-04-01 – 2025-03-31
• Keywords: Actinides / Bioassay / Radiation emergency / Dose assessment / ICP-MS/MS / Cell gas

Outline of Annual Research Achievements

Synthesized faecal sample was used for actinide analytical method development in feces, with the purpose of rapid emergency response on potential radiological/nuclear accidents. High recoveries (>80%) for Np, Pu, and Am/Cm have been obtained after ashing, borate fusion, CaF2 coprecipitation, and chromatographic purification. To increase the signal intensity of actinides in ICP-MS/MS analysis, 7.5 mL/min He has be introduced into the collision/reaction cell, along with the application of APEX-Q/ACM introduction system＋x type lens. The developed method was validated by participating in the annual intercomparison organized by PROCORAD, France.

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

As expectation, bioassay method for the measurement of actinides in faecal sample was developed based on the rapid and sensitive ICP-MS/MS analysis after chemical separation and purification.
The related paper is being prepared and will be submitted in 2023.
In order to communicate with other researchers and obtain the latest information, we also participated in several domestic and international conferences.

Strategy for Future Research Activity

Since the concentrations of actinides in the blood was relatively high just after internal exposure and before decorporation. It is critical to collect and measure blood samples during this short period for the dose assessment to provide critical information for medical treatment. A novel procedure should be established. After the development of bioassay method for the measurement of actinides in faecal sample, the development of bioassay method for the measurement of actinides in blood sample will be performed in this year.

Causes of Carryover

For the second year, materials and reagents for the method development of actinide bioassay in the blood should be purchased. The amount of materials and reagents exceeds the expected amount written in the proposal. Therefore, we save some budget in the first year and would buy necessry materials (e.g., resin cartridge for the purification of actinides in blood) and reagents (e.g., acid for the organic matter decomposition in blood) for the blood experiment in the second year.

Research Products

• [Journal Article] Rapid measurement of actinides in urine by mass and alpha spectrometric methods (2023)
  • Author(s): Guosheng Yang; Jian Zheng; Munehiko Kowatari; Eunjoo Kim; Osamu Kurihara
  • Journal Title: Radiation Protection Dosimetry Volume: - Pages: -
  • DOI: 10.1093/rpd/ncad005
  • Peer Reviewed
• [Journal Article] The new QST bioassay laboratory in Chiba Japan (2022)
  • Author(s): Guosheng Yang; Kotaro Tani; Munehiko Kowatari; Yuki Tamakuma; Masayuki Naito; Eunjoo Kim; Osamu Kurihara
  • Journal Title: Radiation Protection Dosimetry Volume: - Pages: -
  • DOI: 10.1093/rpd/ncac198
  • Peer Reviewed
• [Presentation] Rapid analysis of Sr-90 in small volume of urine by ICP-MS/MS after chromatographic purification (2022)
  • Author(s): Yang, G., Kim, E., Zheng, J., Kowatari, M., Kurihara, O.
  • Organizer: International Youth Nuclear Congress IYNC2022, Koriyama, Japan.
  • Int'l Joint Research
• [Presentation] Rapid fecal and urinary bioassay for the measurement of multiple actinide isotopes (2022)
  • Author(s): Yang, G., Kim, E., Zheng, J., Kowatari, M., Kurihara, O.
  • Organizer: 2022 ARADOS-KREDOS Joint Annual Meeting, Soul, Korea
  • Int'l Joint Research
• [Presentation] Recent advancement in bioassay at QST (2022)
  • Author(s): Yang, G., Kim, E., Zheng, J., Seno, H., Kowatari, M., Kurihara, O.
  • Organizer: 日本放射化学会第66回討論会、東京都
• [Presentation] Development of a new bioassay laboratory at QST (2022)
  • Author(s): Yang, G., Tamakuma, Y., Naito, M., Seno, H., Tani, K, Kim, E., Kowatari, M., Kurihara, O.
  • Organizer: International Conference on Individual Monitoring of Ionising Radiation (IM2022) and Neutron and Ion Dosimetry Symposium (NEUDOS-14), KRAKOW POLAND (online)
  • Int'l Joint Research
• [Presentation] Rapid measurement of actinides in urine by mass and alpha spectrometric methods (2022)
  • Author(s): Yang, G., Kim, E., Zheng, J., Seno, H., Kowatari, M., Kurihara, O.
  • Organizer: International Conference on Individual Monitoring of Ionising Radiation (IM2022) and Neutron and Ion Dosimetry Symposium (NEUDOS-14), KRAKOW POLAND (online)
  • Int'l Joint Research