Extractive scintillating resin for Tc-99 quantification in aqueous solutions

A method utilizing extractive scintillating resin for Tc-99 monitoring in a queous solutions is presented. These extractive scintillators combine analy te selective uptake and scintillating properties to produce dual functional ity analytical resins. These resins were produced by (1) co-located extract ion chromatographic resin and plastic scintillating beads, (2) immobilizing fluors in macroporous polystyrene supports to which chains of monomethylat ed polyethylene glycol have been grafted and (3) co-immobilizing organic sc intillating fluors and a quaternary ammonium extractant (Aliquat-336) withi n macroporous acrylic and polystyrene supports. The first and third resins selectively extract pertechnetate ions from dilute acid whereas the second resin selectively extracts pertechnetate ions from high ionic strength solu tions. These resins were utilized in similar to0.20 ml pore volume columns while 99Tc was continually monitored with commercially available scintillat ion detection systems. Manual and automated microfluidics were used to deli ver sample and reagent solution for loading and elution of the 99Tc. The de tection efficiencies were determined to be 45 and 70% for acrylic and polys tyrene based resins, respectively, and independent of extractant. Minimum d etectable 99Tc concentration using the Aliquat-336/acrylic-based resin was 6.2 Bq.l(-1) for a 50-ml sample and 30-minute count time. The new methodolo gy was applied towards analysis of contaminated groundwater samples and nuc lear waste simulants.