Important consideration:

Important consideration is the type of radiation emitted through the radionuclide especially along with respect to penetrating power, ease of measurement and potential radiation damage. Commonly α emitting isotope is least preferred because of low penetration power related with high ionization and radiation damaging effects. For thick and dense samples, γ emitting radiotracer should be a necessary choice because of its high penetrating power and ease of detection. In principle β emitters might be used as tracer for thin samples such as thin films and surfaces but these are not preferred. In general, β or γ emitters are considered as best choice for chemical studies because of ease of detection by using Geiger-Muller or scintillation counters.