Mn-porphyrin derivatives as an antioxidant for medical devices

It is well known that reactive oxygen species such as O-2(-) and H2O2 induce the biodegradation or cracking of medical devices in vivo or that they are released from inflammatory cells activated by devices to oxidize low-density lipoprotein. Therefore, the development of a novel antioxidant is required to eliminate the reactive oxygen species. In this paper, we report that Mn-porphyrin derivatives containing a macromolecular Mn-porphyrin are relatively stable compounds that can eliminate O-2(-) and/or H2O2 The dismutation of O-2(-) in the porphyrins was determined using a cytochrome c-assay by the xanthine/xanthine oxidase system and using the stopped-Bow kinetic analysis technique. The possibility of porphyrins as scavengers of H2O2 was evaluated by in situ measurement with a Clark electrode. As a result, it has been found that Mn-porphyrin derivatives may be a vastly better scavenger of reactive oxygen species in vivo.