The neutron activation analysis of platinum (an element which yields a short-lived radioactive species, 199Pt) in biological tissue has been demonstrated by the analysis of the longer lived radioactive 199Au daughter of the 199Pt. The longer lived gold allows the radiochemical separation of sodium from the trace elements present in biological tissue and permits a more leisurely counting technique. Linearity of the net counts per µg of platinum versus µg of platinum added has been demonstrated. This technique provides a useful method for the analysis of any element whose short-lived radioisotope decays to a longer lived daughter.