title: A new system for washing ion-exchange paper disks used in radiochemical enzyme assays.
abstract: A new device has been developed for the removal of radioactive substrate from ion-exchange paper disks, leaving ionized product bound to the paper. It has a number of important advantages over older methods of washing the ion-exchange paper: (1) It is much more thorough and efficient; background absorption of unionized material is reduced to relatively low levels. (2) Fragile media such as DEAE-substituted paper (DE81) are not subjected to the erosive effects of stirrers or agitators. (3) The disks remain organized throughout the sample application and washing procedure, eliminating need for time-consuming sorting of wet radioactive disks after washing. A larger number of assays can therefore be processed conveniently at one time. (4) Radioactive nucleosides and other adsorbable substrates are collected in a cartridge, eliminating the handling and sink-disposal of large volumes or excessive quantities of radioactive materials.
mesh_terms: D002852:Chromatography, Ion Exchange / Q000295:instrumentation / Q000379:methods; D002853:Chromatography, Liquid / Q000295:instrumentation* / Q000379:methods; D002854:Chromatography, Paper / Q000295:instrumentation / Q000379:methods; D004798:Enzymes / Q000032:analysis*; D009711:Nucleotides / Q000032:analysis; D010770:Phosphotransferases / Q000032:analysis; D011854:Radiochemistry
chemical_list: D004798:Enzymes; D009711:Nucleotides; D010770:Phosphotransferases; C021892:nucleoside phosphotransferase