Dye-Doped Polymeric Particles for Sensing and Imaging - Advanced Fluorescence Reporters in Chemistry and Biology - page 200

Fig. 3 Chemical structures and typical spectral properties of the common luminescent emitters
used for staining of polymeric beads
Finally, luminescent europium(III) and terbium(III) chelates feature very narrow
emission bands and large Stokes shifts. They possess long luminescence decay
times of several hundred microseconds, but the emission is only minor quenched by
oxygen. Thus, these chelates are primarily used for labeling purposes. The lumi-
nescence is also highly temperature-dependent which makes these dyes promising
candidates for optical temperature sensing and imaging. Notably, most of these
chelates are excitable in the UV region only, which may compromise their applica-
bility. However, some of the europium(III) chelates reported recently possess bright
blue light-excitable luminescence and were used for staining polymeric beads.
2.3 Functional Additives
Apart from polymers and indicators, the beads can contain a variety of other
components that improve their properties or provide additional functionalities.
For example, addition of titanium dioxide nanoparticles significantly increases
the brightness of the beads due to light scattering [ 5 ]. The plasmonic enhancement