Stability and reproducibility of gel-suspension samples for the liquid scintillation counting of14C using N-lauroyl-L-glutamic-α,γ-dibutylamide

Abstract

Stability and reproducibility of gel-suspension samples were investigated in order to evaluate the characteristic feature of the gel-suspension method for J4C activity measurement. Commercially available gelling agent, N-lauroyl-L-glutamic-c~,~'-dibutylamide, was used for the gelformation of the samples. No change of the counting rate for the gel-suspension sample was observed for more than 2 years after the sample preparation. Four samples used for checking the reproducibility of the sample preparation method. The same values were obtained for the counting rate of 14C activity within the counting error. No change of the counting rate was observed for the "re-gelated" sample. These results show that the gel-suspension method is appropriate for the 14C activity measurement by the liquid scintillation method and is useful for a long-term preservation of the sample for repeated measurement.