R.E. Brown

Use of tertiary alkyl primary C12C14 amines for the assay of C14O2 by liquid scintillation counting

Abstract The use of Primene 81-R (Rohm and Haas Co., Philadelphia, Pa., U.S.A.), a mixture of tertiary alkyl primary long chain (C12C14) amines, as a reagent for the quantitative trapping and scintillation counting of C14O2 is described. The 160°C in vacuo distillation of Primene 81-R yields a colorless distillate which when diluted with methanol to a molarity of from 0·25 to 2·0 rapidly and quantitatively traps CO2. The Primene-C14O2 complex is stable at 25°C and compatible with scintillation fluid composed of 3 g 2,5-diphenyloxazole per liter of toluene. Primene 81-R causes little or no quenching when used in the concentrations recommended.