Fluorescence based oxygen sensor systems

A method for making a composition for sensing oxygen or an oxygen-related analyte in a medium, said method comprising the following steps:

• (a) mixing a luminescent platinum group metal polyaromatic chelate complex capable of having its luminescence quenched by oxygen with one or more precursors of a polymeric matrix that is permeable to oxygen,
• said complex having the following general formula
• M+L1L2L3,
• wherein M+ is Ru2+, Os2+;
• Ir3+, or Rh3+;
• ligands L1 and L2 are identical or different and represent an optionally substituted bidentate phenanthroline or diphenylphenanthroline ligand or an optionally substituted cyclometallated bidentate phenylpyridine or a benzo[h]quinoline ligand;
• ligand L3 is a bidentate diphenylphenanthroline ligand substituted by one or more functionalized linker arms capable of covalently linking the complex to the matrix material;
• said functionalized linker arm having the structure A-X,
• where A is comprised of a group selected from the group consisting of a covalent bond, O, C(O)O, an optionally substituted methylene group, an optionally substituted carbon chain comprising 2-20 carbon atoms, and combinations thereof, wherein said carbon chain optionally comprises one or more oxygen atoms, nitrogen atoms, sulfur atoms, silicon atoms, heterocyclic groups, or aryl groups, and
• where X is selected from the group consisting of a hydroxy, an alkoxy, a halo, a carboxy, an acetoxy, a phenol, a siloxane, and a vinyl group,
• (b) adding a catalyst to the mixture of step (a), and
• (c) activating said catalyst to form a polymeric matrix which is covalently bonded to said complex by said linker arm.

A platinum group metal polyaromatic chelate complex having the following general formula

• M+L1L2L3
• wherein
• M+ is Ru2+, Os2+, Ir3+, or Rh3+;
• ligands L1 and L2 are identical or different and represent an optionally substituted bidentate diphenylphenanthroline ligand;
• ligand L3 is a bidentate diphenylphenanthroline ligand substituted by one or more functionalized linker arms capable of covalently linking the complex to the matrix material;
• said functionalized linker arm having the structure A-X,
• where A or X is comprised of one or more carbon-carbon double bonds or both A and X are comprised of one or more carbon-carbon double bonds.