A Near-Infrared Luminescent Label Based on YbIII Ions and Its Application in a Fluoroimmunoassay

The combination of the long-lived, spectrally pure emission of YbIII ions with the outstanding light-absorbing capabilities of organic dyes gives photoluminescent lanthanide complexes that are interesting candidates for use as a new class of luminescent labels for molecules of biomedical interest. The water-soluble complex shown can be covalently attached to biomolecules and used in a model medical diagnostic test.