Abstract: A method for preparing a .sup.195m Au-containing liquid is provided. In the method, .sup.195m Hg is adsorbed on an adsorption agent and then the daughter radioisotope .sup.195m Au is eluted from the adsorption agent with an eluant containing a gold-complexing agent. The adsorption agent comprises a mercury ion-binding material having a substantially stronger adsorption affinity for mercury ions than for gold ions.Also disclosed are a radioisotope generator capable of producing a .sup.195m Au-containing liquid and a process for conducting a radiodiagnostic examination on a warm-blooded animal using a .sup.195m Au-containing liquid.

Abstract: The invention relates to radiolabelled metallocene derivatives of the general formula ##STR1## wherein Mc is a metallocenyl group with a radioactive central atom,R is a carbonyl or methylene group,R.sub.1 is a hydrogen atom or an alkyl group having 1-4 carbon atoms,A is a carboxy group or a pharmaceutically acceptable salt thereof, or an alkoxycarbonyl or alkanoyl group having 2-5 carbon atoms, andn is 1-4.The invention also relates to radiodiagnostic compositions comprising said radiolabelled metallocene derivatives and to a method of performing a radiodiagnostic examination, in particular of examining the renal function.