ABSTRACT
Objective To investigate several related problems possibly affecting the measurement results in the experiment of 125I-FSH in vitro cells uptake by domestic GC-1200 gamma RIA counter.Methods Before entering the measuring room,the sample was performed the background measurement.CPM measured in the different locations of same measurement frame and the different locations in unmeasured area were performed the statistical comparison.Results In high count,the influence of single sample reaching 1.9 ×106CPM on the adjacent low counting tube count was 7%;its influence on low counting tube count in adjacent detector was 7.33%;all samples were arranged from high to low order and the high count sample holder was placed on the measured location close to the detector,its influence on low counting tube count was 5.33%.Conclusion The domestic GC-1200 γ RIA counter is suitable for the measurement of the in vitro cell uptake experiment of 125I nuclear labeling.