Synthesis of a sugar-functionalized iridium complex and its application as a fluorescent lectin sensor

Syntheses of two [Ir(bipy)(Ppy)2] complexes functionalized with mannose and galactose are reported. The complexes were characterized by NMR and mass spectrometry. Fluorescence studies have shown enhanced interaction of the mannose-functionalized complex with mannose specific lectin concanavalin A whereas the galactose-functionalized complex did not show any interaction. The binding constant (2.9 × 105 mol−1) was determined from the fluorescence spectroscopic data.