pubmed-article:7780376 | pubmed:abstractText | A rapid synthesis of the chlorofluorocarbon replacement compound 1,1,1,2-tetrafluoroethane (HFA-134a) was identified and utilized to prepare 99+% radiochemically pure [18F]HFA-134a in 20-35% radiochemical yield. Four rats were then exposed to no-carrier-added (NCA) [18F]HFA-134a, and monitored via coincidence detection. Following withdrawal of the test atmosphere of [18F]HFA-134a, the mean half-life of [18F]HFA-134a in four rats was determined to be 7.8 +/- 1.5 min following a 10 s exposure and 8.1 +/- 1.7 minutes following a 10 min exposure. | lld:pubmed |