Pulse labelling
Pulse labelling is a biochemistry technique of identifying the presence of a target molecule, by 'pulsing' the sample, in other words, by labeling the sample with a radioactive compound. This is mainly done to identify the stage at which the messenger RNA is being produced in a cell. In this the pulse of H atom is pulsed for a period of around 2 mins to detect the newly formed mRNA during that period.