Determination of Ultra-Low Levels of 239Pu and 240Pu in Biological Samples
10.19756/j.issn.0253-3820.231483
- VernacularTitle:生物样品中超低水平239Pu和240Pu的分析
- Author:
Yong-Chang WANG
1
;
Meng-Ting ZHANG
;
Xiao-Lin HOU
Author Information
1. 中国科学院地球环境研究所,黄土与第四纪地质国家重点实验室,西安加速器质谱中心,西安 710061;中国科学院大学,北京 100049
- Keywords:
Plutonium isotope;
Biological samples;
Rapid ashing;
Extraction chromatography;
Inductively coupled plasma-mass spectrometry
- From:
Chinese Journal of Analytical Chemistry
2024;52(5):706-716
- CountryChina
- Language:Chinese
-
Abstract:
In this work,a reliable analytical method for ultra-low 239,240Pu in biological samples was developed.Sodium carbonate and magnesium acetate were used as saponification agent and ashing aid,respectively,and then Fe(OH)2-Fe(OH)3 was used for co-precipitation separation and enrichment of plutonium extracted from the ashing samples.Then aluminum nitrate was used as a masking agent to eliminate the interference of a large amount of phosphorus in the loading solution on plutonium during the anion exchange separation process.The results showed that the average recovery of plutonium was more than 73%and the decontamination factor for 238U was 3.3×104-5.4×105 in biological samples.The ultimate sample introduction technology(APEX-Ω)was used in determination of plutonium isotopes by inductively coupled plasma mass spectrometry(ICP-MS/MS)with NH3-He as the collision/reaction gas.The 242Pu standard added before sample separation was used as the yield tracer and isotope diluent to calculate the concentration of 239Pu and 240Pu in samples.This method not only effectively suppressed the 238U peak tail and 238U1H+interference,but also greatly improved the analytical sensitivity of plutonium from 850 cps/(pg/g)(ICP-MS/MS)to 8000 cps/(pg/g)(APEX-ICP-MS/MS).The detection limits of 239Pu and 240Pu in 3.5 kg fresh fish samples were as low as 2.56×10-4 mBq/(kg·wet)and 7.33×10-4 mBq/(kg·wet),respectively.The detection limits of 239Pu and 240Pu in 300 g fresh seaweed samples(30 g dry weight)were 2.98×10-3 mBq/(kg·wet)and 8.55×10-3 mBq/(kg·wet).The concentrations of 239Pu and 240Pu in marine biological samples from the China Sea have been successfully analyzed by using the established analytical method.
