crti 06-0230 rd: rapid methods for emergency bioassay chunsheng li, health canada gary kramer,...
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CRTI 06-0230 RD: Rapid Methods for Emergency Bioassay
Chunsheng Li, Health CanadaGary Kramer, Health CanadaBaki Sadi, Health Canada
Diana Wilkinson, DRDC-Ottawa
Kui Yu, National Research CouncilYi Cui, National Research Council
Edward Lai, Carleton UniversityAmy Hrdina, Carleton UniversityNegar Bahraini, Carleton University
Project Introduction
• Project Background - Rapid bioassay is required to screen large population
- Po-210 and Sr-90 are two high risk but “difficult” radionuclides
• Design Objectives - Detection Limit: 10% of derived urine action level (Bq/L) based on
500 mSv committed effective dose equivalent from inhalation
- Urine throughput: 120 samples in the first 48 hours per system
- Feces throughput: 20 samples in the first 48 hours per system
Project Tasks
• Developing rapid methods for measuring Po-210 and Sr-90 in bioassay samples using “traditional approach”
- Based on currently available techniques
- Focusing on rapidness, sensitivity, accuracy, repeatability, and
field deployability etc
- Studying the metabolism of Po-210
• Exploring the application of new materials and new technology to radiation assessment
- Application of quantum dots in radiation measurement
- Application of magnetic nano-parrticles in sample preparation
Achievements To Date (I):Rapid Method for Sr-90 Bioassay
• RFigure 4: This spectrum shows yttrium-90 growth. From top to bottom: no yttrium, yttrium growth after 1 hour, 10 hours, and 96 hours respectively. Spectra from liquid scintillation counter Tri-Carb 3180 TR/SL.
Urine sample
Acidification & Transferring(5 minute)
Preconditioning & decolourization(10 minutes)
Complexation & pH adjustment(5 minutes)
Anion exchange separation(15 minutes)
Cocktail mixing &Liquid scintillation measurement
(15 minutes)
Baki, Sadi, Chunsheng Li, Sara Jodayree, Vera Kochermin, Edward Lai, Gary Kramer “A rapid bioassay method for the determination of Sr-90 in human urine samples”. Submitted to Health Physics, 2009
Chunsheng Li, Baki Sadi, Gerry Moodie, Joseph daka, Edward Lai, Gary Kramer “Field deployable Technique for Sr-90 emergency bioassay”. Sumitted to Radiation Protection Dosimetry, 2009
Sample 1 2 3 4 5
Urine (g) 19.9 19.0 19.1 19.7 19.2
90Sr Spiked (Bq) 46.7 44.8 45.1 46.4 45.4
Results from Triathler (Bq) 51.2 ± 0.3 49.4 ± 0.3 51.2 ± 0.3 49.7 ± 0.3 52.3 ± 0.3
Bri (%) 9.6 10.3 13.5 7.1 15.2
Br (%) 11.1
SB (%) 3.2
sisiiri CCCB /)(
n
i
rir N
BB
1
Where: Ci = the measured activity in each replicate sample i;
Csi = the spiked activity in each replicate sample i;
Bri = the relative bias of the measurement for replicate sample i;
Br = the relative bias of the measurement for the spiked level;
N = the number of replicates for the spiked level, in this work, N = 5.
11
2
N
BBS
N
irri
B
Achievements To Date (II):Application of QDs
Emission Wavelength (nm)400 12001000800600 1400
CdSCdS
CdSeCdSe
InP
HgS
CdTeCdTeZnSe
InAs
HgTe
• A
Robert Z Stodilka, Jeffrey JL Carson, Kui Yu, Md. Badruz Zaman, Chunsheng Li, and Diana Wilkinson “Optical Degradation of CdSe/ZnS Quantum Dots upon Gamma-Ray Irradiation”, J. Phys. Chem. C. 2009, 113, 2580-2585.
Yu, Kui; Cui, Yi; Zaman, Md. Badruz; Wilkins, Ruth; Li, Chunsheng; Wu, Xiaohua; Ouyang, Jianying; “Optical Response of CdSe Quantum Dots to Cs-137 γ Radiation” J. Nanoscience and Nanotechnology. 2009, Accepted.
Achievements To Date (III):Application of MNPs in Bioassay
Fe3+ + H2ODeprotonation
Fe(OH)x3-x
Fe2+ + H2ODeprotonation
Fe(OH)y2-y
Oxidation
DehydrationpH ~ 9
Fe3O4 Magnetite
Fe3O4 Fe3O4
OH
OH
OH
1. MAA2. (NH4)2S2O8
in H2O treated with SDS, 70oC 2 h
Fe
O
O
NIP-PMAA-coated magnetic particles
NIP-coated magnetic particles
Magnetic particles
Achievements To Date (IV):Metabolism of Po-210 in Rats
• Primary: volatile Po-210 species in excreta - Implicating the accuracy in radiation dose assessment - Implicating in radiation protection - Providing information for bioassay method development
• Secondary: IR imaging – change in thermal profile for invasive screening
• Secondary: excretion and bio-kinetics - Excretion via urine - Excretion via feces - Distributions in tissues/organs
Daily Volatile Excretion (All CPM Corrected to March 01, 2009)
0
5
10
15
20
25
30
35
40
45
50
Day 2 Day 3 Day 4 Day 5
Days
Act
ivit
y (C
PM
)
Low Dose
High Dose
THE
END