The radionuclide large demand is due to its desirable nuclear properties, the huge amount of ^99mTc-labelled compounds and the existence of generators which make ^99mTc available far from any production centre.

A radionuclide generator is a system by which the parent, an unstable nucleus, produces by radioactive decay a radioactive daughter of shorter half live. In the case of ^99mTc generators the parent is Molybdenum (⁹⁹Mo) with 66 h half life, while the product ^99mTc is 6 h half life.

Objectives. The Radioisotope Production Laboratory from Chilean Nuclear Energy Commission, CCHEN, delivers, on a daily base, ^99mTc to nuclear medicine centers located in the Metropolitan Region (MR). The Laboratory is unable, however, to deliver activities to other country's centers far from MR because its production process. To resolve this situation, CCHEN decided to initiate a project to manufacture and deliver ⁹⁹Mo - ^99mTc generators. With this, in the near future, Chile will be part of the international community managing this technology.

Materials and Methods. The manufacturing process is based on selective adsorption of ⁹⁹Mo on aluminium oxide (Al₂O₃) whereas weakly bounded ^99mTc, produced by 99Mo decay, is easily on a daily basis eluted from alumina. This generator is easy to operate being produced in a closed system designed to warrant sterility and a high purity product.

Results and Conclusions. The alumina preparation, Mo conditioning and the columns characteristics are determinant factors in the manufacturing of ^99mTc-Generators. With the alumina treatment retention of ⁹⁹Mo near to 90% has been achieved. The ^99mTc elution efficiency, in the form of pertechnetate (TcO^-₄), is over 80%. Based on these results, a preproduction batch and the subsequent production of 99mTc generators is expected to by the end of last quarter of 2004.