Luminescent characteristics of tris(2,2′‐bipyridine)‐ruthenium(II) adsorbed in a silk fibroin membrane

<jats:title>Abstract</jats:title><jats:p>The emission characteristics of the excited state of tris(2,2′‐bipyridine)ruthenium(II), Ru(bpy)<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/tex2gif-stack-1.gif" xlink:title="urn:x-wiley:0025116X:media:MACP021920717:tex2gif-stack-1" />, adsorbed on a silk fibroin membrane is studied. The life time of the excited state of the adsorbed Ru(bpy)<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/tex2gif-stack-2.gif" xlink:title="urn:x-wiley:0025116X:media:MACP021920717:tex2gif-stack-2" /> is unusually longer (1 000 ns) than that of Ru(bpy)<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/tex2gif-stack-3.gif" xlink:title="urn:x-wiley:0025116X:media:MACP021920717:tex2gif-stack-3" /> in aqueous solution (598 ns). The excited state of the adsorbed Ru(bpy)<jats:sub>3</jats:sub><jats:sup>2+</jats:sup> is quenched by oxygen when dipped in methanol, but not in water. The quenching by oxygen in methanol follows the Stern‐Volmer equation. The luminescent characteristics of the adsorbed Ru complex is discussed in terms of binding in hydrophobic domains composed of tyrosine residues of the protein.</jats:p>