RARE-EARTH CHELATES AS FLUORESCENT MARKERS IN CELL-SEPARATION AND ANALYSIS

The synthesis of a novel series of functionalized macrocyclic complexes of the lanthanide (III) ions is reported. The Eu (III) complexes possess a set of properties (water solubility, inertness to metal release, ligand-sensitized luminescence, reactive peripheral functionalities) that make them suitable as luminescent markers for biosubstrates. Currently employed organic fluorophores give efficient signal production, but this is accompanied by interference from background fluorescence and, if multiple fluorophores are used, from spectral overlap. The long lifetimes and narrow-band emissions of the luminescent lanthanide complexes will minimize background interference; however, long lifetimes will also result in a significantly reduced signal for flow cytometry or cell sorting.