Rapid enzyme assay technique utilizing radioactive substrate, ion-exchange paper, and liquid scintillation counting

The assay technique consists of determining a labeled anionic product as the radioactivity remaining on anionexchange paper as measured by direct liquid scintillation counting of the paper after elution of the labeled nonionic substrate from the paper with water. Phosphorylations catalyzed by galactokinase and hexokinase are employed as examples. (auth)