Radiometric Precipitation in Filter Paper: a Rapid Method of Micro-analysis

Abstract

A RADIOACTIVE material can usually be detected and quantitatively measured by simple instrumental methods at levels much below those accessible to other analytical techniques. In theory, if an inactive material reacts quantitatively with the active material and the compound formed can be separated from the unreacted activity, then the inactive material also can be analysed at the same low levels. With this in mind, several workers^1,2 have reviewed the theory of radiometric analysis and considerable progress has been made in its application^3–6. In most cases, however, the difficulty of achieving clean phase separations at μgm.-levels is very great. In addition, to achieve reasonable precision and speed, it has nearly always been necessary to count the excess of unreacted activity rather than the compound formed; a procedure which reduces greatly the sensitivity of the method.