Patent ID: 7368570

Claim:
An organometallic singlet oxygen photosensitizer, comprising a metal and one or more ligands, wherein at least one of said ligands has a carbon atom that is covalently bonded to the metal, comprising the formula (C^X) n MY m L p where M is a metal; n+m is 3 when M is trivalent or n+m is 2 when M is divalent; Y is a monoanionic ligand; L is a neutral ligand; or optionally when M is Ir(III) then Y and L are absent; C^X is a bidentate cyclometallated ligand wherein each C^X is the same or different; and X is N, O, S, P or C, wherein at least one of said C^X, Y or L ligands is further coupled to a moiety that can bind to a biomolecule, a cell or biological tissue.