Question

Explain the uses of radioisotopes with reference to autoradiography and antibodies for localizing specific molecules in the cell

Answer 1

One of the important uses of radioactivity in cell biology is to localize a radioactive compound in sections of whole cells or tissues by autoradiography. In this procedure living cells are briefly exposed to a pulse of a specific radioactive compound and then incubated for a variable period - to allow them time to incorporate the compound - before being fixed and processed for light or electron microscopy. Each preparation is then overlaid with a thin film of photographic emulsion and left in the dark for a number of days, during which the radioisotope decays.