A 195Hgsup(m)-195Ausup(m) generator for use in first-pass nuclear angiocardiography

The development of a mercury-195m/gold-195m radionuclide generator system is described, together with the results of preliminary experiments in animals and in man. The daughter radionuclide has a half-life of 30.5s with a principal gamma emission at 262 keV, ideal for use with the multicrystal camera but suitable also in conjunction with the Anger design. The half-life of the parent radionuclide is 40 h. The eluant in current use is 2.5 mM sodium cyanide, the column being stored under 2% sodium nitrate solution when not in use to prevent radiation damage. Generators capable of delivering 550 MBq of 195Ausup(m) in a 0.4 ml bolus have been used for first-pass nuclear angiocardiography, the half-life being long enough to permit administration via peripheral intravenous injection. The radiation dose associated with this radionuclide is much lower than that from conventional 99Tcsup(m)-labelled radiopharmaceuticals, permitting multiple sequential studies, even on children. (author)