Photophysics bioprobes

Some examples are emphasized in the next chapter Lanthanides Luminescence Applications). The luminescence spectra of various lanthanide ions will be given and several applications using luminescent lanthanide complexes will be presented. Luminescent Bioprobes, some practical data and a case of study will be presented. The properties of a series of lanthanide complexes (i.e., with ligands that share a common architectme) will be expUcated both from a physicochemical and from a photophysical point of view. It will be demonstrated that these complexes are highly stable and present interesting photophysical properties, so that their application as bioprobe can be imdertaken. 

Eu2(L )3] was specifically designed to shift the wavelength (from 330 up to 365 nm), which results in a loss of quantum yield (9%), but proved to be good enough in time-resolved spectroscopy and a better bioprobe than [Eu2(L )3] for confocal microscopy. [Eu2(L )3] with x = 4, 6 where two other probes developed for the same purpose, but their physicochemical and/or photophysical properties were not good enough to consider ftiem for any application. 

Hayek A, Bolze F, Bourgogne C, Baldeck CL, Didier P, Amtz Y, Mely Y, Nicoud JF (2009) Boron containing two-photon absorbing chromophores. 2. Fine tuning of the one- and two-photon photophysical properties of pyrazabole-based fluorescent bioprobes. Inorg Chem 48 9112-9119... 

Table 4.4 Photophysical properties of the luminescent bioprobes used for multiparameter detection of leucocytes [46]...

Encapsulation of the chelates into nanopartieles often results in further improvements of their photophysical properties [219,220]. We have also seen above that relatively modest quantum yields can be compensated by introducing several emitting ions in one probe. This is achieved in luminescent metal-organic frameworks [221] or dendrimeric complexes [214] which then present attractive properties, including multifunctionality and nanoscale processability, for chemical sensors and bioprobes. 

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