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Strontium Extraction from Urine Samples. Westinghouse Savannah River Company Gerald D. Levi, Jr. 1. Strontium Extraction from Urine Samples. Introduction Strontium Analysis Process Flow Current Strontium Extraction Method Method Enhancements Summary. 2. Sample Receiving Acidification
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Strontium Extraction from Urine Samples Westinghouse Savannah River Company Gerald D. Levi, Jr. 1
Strontium Extraction from Urine Samples • Introduction • Strontium Analysis Process Flow • Current Strontium Extraction Method • Method Enhancements • Summary 2
Sample Receiving Acidification Co-Precipitation Clean-Up Ion Exchange Strontium Analysis Process Flow 3
Current Strontium Extraction Method • Acidify Samples with 10 mL of 8 M HNO3 • Condition Sr resin with 5 mL of 8 M HNO3 • Transfer acidified samples onto Sr resin • Rinse Sr resin with 5 mL of 8 M HNO3 • Rinse Sr resin with 5 mL of 3 M HNO3 - 0.05 M Oxalic Acid • Rinse Sr resin with 5 mL of 8 M HNO3 • Rinse Sr resin with 10 mL of 0.05 M HNO3 • Heat lamp dry samples onto planchets • Analyze sample planchets by gas proportional counting 9
Method Enhancements • Removed a rinse step with 5 mL of 8 M HNO3 - Save approximately 10-20 minutes a batch • Matrix matched the calibration standards and samples - More representative detector efficiency • Replaced the gravity flow method with a vacuum method - Reduced the batch extraction time by a factor of two • Switched from Columns to Cartridges - Improved spike recovery from 70% + 10 % to 85% +10% 11
Summary • Routine recoveries of 75% - 95% • Minimized Inconclusive Analyses (IA) and Reruns due to higher recoveries • Reduced batch extraction time from 4 hrs. to 2 hrs • Cost savings due to freeing up technician time to complete other lab tasks 14
Acknowledgement • Sherrod Maxwell • David Fauth • Christy Posey • Ginny Lackey 15