ABSTRACT
Technetium, number 43 in the periodic table, was the first element to be made artificially. Its discovery in 1937 was followed by a lengthy period in which it remained somewhat of a scientific curiosity. A direct result of the application of 99mTc, in conjunction with instruments capable of mapping its distribution within the human body, is the universal acceptance of nuclear techniques in medical diagnosis. Technetium-99m occupies a position of pre-eminence as the most frequently used radionuclide in routine clinical practice. An important property of 99mTc, essential to reducing radiation exposure, is its half-life of 6 hr. There are several methods of separating 99mTc from parent 99Mo and in most cases the choice of method is dictated by the mode of preparation and hence quality of the 99Mo. There are several methods of separating 99mTc from parent 99Mo and in most cases the choice of method is dictated by the mode of preparation and hence quality of the 99Mo.
