Deuterohemin IX is an intermediate for the synthesis of Protoporphyrin IX Dimethyl Ester-d6 (P839127), which is the labelled version of Protoporphyrin IX P(P838900). Protoporphyrin IX (PPIX) is ubiquitously present in all living cells in small amounts as a precursor of heme and PPIX-based strategies have been used for cancer diagnosis and treatment. It can be used in biological study for role of protoporphyrin IX in skin photosensitivity, biliary stones, hepatobiliary damage, liver failure and cancer diagnosis and treatment in human.