Commercial Production of Radioisotopes for Nuclear Medicine, 1970-1980

The first small cyclotrons were installed for commercial production of radioisotopes at New England Nuclear Corporation, Billerica, Massachusetts, and at Medi-Physics, Emeryville, California. Both machines were Cyclotron Corporation Cs-22 multiple particle, fixed energy cyclotrons. In the ten years that followed, the total number of commercial radioisotope producing small accelerators has grown to ten, with four more projected for 1981. The beam energy requirement for the first accelerators was modest; 22 MeV protons, 12 MeV deuterons, 24 MeV He-4, and 31 MeV He-3; and commercial radioisotope production for nuclear medicine utilized all four particles. The first product available from cyclotron production was fluorine-18 from the 16O(3He, p)18F reaction. Injected intravenously as no-carrier-added Na18F, the radionuclide quickly concentrated in bone, providing the nuclear medicine physician with diagnostic information on skeletal abnormalities including metastatic bone disease. Following in quick succession were 67Ga from 68Zn(p, 2n)67Ga, 111In from 112Cd(p, 2n)111In, 43K from 40Ar(¿, p)43K, 123I from 122Te(d, n)123I, and 81Rb from 82Kr(p, 2n)81Rb. The next few years saw one radionuclide, 43K, disappear from the marketplace, and two others, 18F and 81Rb, disappear, and then reappear, although not for the purposes originally intended. More recently, the widespread demand for 201Tl for imaging myocardial perfusion has led to increased requirements for beam energies higher than those from the original small cyclotrons.