MOLYBDATE ION MO-99 is used as a precursos of Tc-99, the last is the most commonly used medical radioisotope. Mo 99 is primarily extracted from U-235 fission products, and then undergoes β decay with a half-life of 66 hours, and the Tc-99 is then chemically extracted. A few micrograms of Mo-99 can produce enough Tc-99 to perform as many as 10,000 tests.

o-Phenylenediamine is a chemical intermediate used in the synthesis of fungicides, corrosion inhibitors, pigments, and pharmaceuticals. It is also used to remove elemental sulfur in mining ores, and to remove aldehyde color formers in polymeric products. o-Phenylenediamine is also a substrate of enzyme-catalyzed oxidation reactions. 2,3-Diaminophenazine was detected as a product of peroxidase-catalyzed oxidation of o-phenylenediamine dihydrochloride in ELISA procedures. o-Phenylenediamine is a methaemoglobin-producer. Oral administration of o-phenylenediamine led to significantly increased incidences of liver tumors in the rat and mouse.