Liquid Scintillation Counting Methodology for ⁹⁹Tc Analysis: A Remedy for Radiopharmaceutical Waste

Abstract

This paper presents a new approach for liquid scintillation counting (LSC) analysis of single-radionuclide samples containing appreciable organic or inorganic quench. This work offers better analytical results than existing LSC methods for technetium-99 ((99g)Tc) analysis with significant savings in analysis cost and time. The method was developed to quantify (99g)Tc in environmental liquid and urine samples using LSC. Method efficiency was measured in the presence of 1.9 to 11 900 ppm total dissolved solids. The resultant quench curve proved to be effective for quantifying spiked (99g)Tc activity in deionized water, tap water, groundwater, seawater, and urine samples. Counting efficiency was found to be 91.66% for Ultima Gold LLT (ULG-LLT) and Ultima Gold (ULG). Relative error in spiked (99g)Tc samples was ±3.98% in ULG and ULG-LLT cocktails. Minimum detectable activity was determined to be 25.3 and 22.7 mBq for ULG-LLT and ULG cocktails, respectively. A preconcentration factor of 1000 was achieved at 100 °C for 100% chemical recovery.

Fully Automated System for 99Tc Monitoring in Hospital and Urban Residues: A Simple Approach to Waste Management

“…The proposed system offers better analytical results than existing LSC methods for 99 Tc determination with significant savings in analysis cost and time. 5 Flow analysis techniques have allowed the automation of a huge number of analytical protocols, providing the partial or complete automation of the analytical methods. This automation allows a significant decrease in time of analysis, the reduction of sample and reagent consumption, and a minimal handling of samples and standards, improving the safety of the analyst.…”

“…Recently, a novel methodology to perform the analysis without purification of matrix components was successfully applied to radiopharmaceutical waste. The proposed system offers better analytical results than existing LSC methods for 99 Tc determination with significant savings in analysis cost and time …”