Lanthanide Luminescence for Biomedical Analyses and Imaging

The problematic issues of lanthanide luminescent bioprobes (LLB) from the standpoint of their photophysical and biochemical properties are studied. Quenching of the lanthanide luminescence by high-energy vibrational overtones is a major concern in the design of luminescent probes. On the other hand, it allows one to assess the number of water molecules q interacting in the inner coordination sphere from lifetimes measured in water and deuterated water. Several phenomenological equations have been proposed, based on the assumptions that O-D oscillators contribute little to deactivation and that all the other deactivation paths are the same in water and in deuterated water. Efficient lanthanide luminescent bioprobes must meet several stringent requirements, chemical, photophysical, and biochemical. A growing number of bioanalyses require specific targeting of the analyte, and therefore the lanthanide luminescent probes have to be fitted with adequate functionalities able to couple with biological material.