Improved Urinary Excretion Test for Assay of Intrinsic Factor. II. Sensitive Counting Technic ∗

Abstract

Summary

Measurement of gamma radiation of low specific activity contained in relatively large volumes can be adequately performed with the use of a specially designed beaker which fits into the well and covers the cross section of a well-type scintillation counter. The increase in sensitivity obtained with this beaker allows the administration of smaller oral doses of vit. B₁₂C_{o 60} for additional assays using the same patient for the urinary excretion tests for intrinsic factor. In addition, no concentration of the urine sample is necessary and less counting time is required.