Fingerprint signatures of lanthanide circularly polarized luminescence from proteins covalently labeled with a β-diketonate europium(iii) chelate

Fingerprint signatures of circularly polarized luminescence (CPL) are observed from Staphylococcus aureus nuclease (SNase), bovine serum albumin (BSA), and insulin (Ins) labeled with europium(III) complexes containing a β-diketonate ligand, where SNase shows a virtually opposite CPL sign compared to those of BSA and Ins.