Luminescent chelates

Chen, J., and Selvin, P.R. (1999) Thiol-reactive luminescent chelates of terbium and europium. Bioconjugate Chem. 10, 311-315. 

The emission of luminescent chelates can be increased by having a large excess of structurally identical non-emissive chelates. An example of non-emissive chelates are those of Gd3+, Y3+. For example, the luminescence of Eu3+-/3-diketone can be increased by 1000-fold by the addition of Gd3+ chelates. 

Covalent coupling of a lanthanide luminescent chelate to bioactive molecules such as peptides, proteins, or nucleic acids makes use of the chemically reactive groups of these molecules. The most common ones are aliphatic a- or s-amines. A typical example of s-amine is lysine, the pRa of which is 9.2 so that it reacts cleanly above pH 8 to yield stable... 

Taking into account the luminescent chelates developed for bioanalyses (mainly immunoassays), most of the presently available LLBs fall into the following classes (i) polyaminocarboxylates (Latva et al., 1997 Takalo et al., 1997), (ii) bipyridine-based cr) tates (Guillaumont et al.,... 

As has been described in [ Basics of Lanthanide Photophysics , BiinzU, Eliseeva] and in [ Stable Luminescent Chelates and MacrocyclicCompounds , Mathis, Bazin], luminescent lanthanide complexes contain an antenna chromophore that serves to efficiently absorb excitation light and transfer this energy to the incorporated lanthanide ion that can then exhibit its photoluminescence. In this case, the overall luminescence quantum yield,, ot, is given by the product of the photosensitisation efficiency Tjsens, which gives the overall antenna-to-lanthanide energy transfer efficiency, and the intrinsic photoluminescence quantum yield of the lanthanide ion, [Pg.137]

Soini E, Henunila 1 (1983) Luminescence spectroscopy assay means with luminescent chelate of europium. US Patent 4,374,120A... 

Quantum yields of the luminescent chelates pubhshed to date are on the order of 8-10% and 40-60% for Eu and Tb , respectively. Some representative examples are given in Table 4.5 for Tb chelates. It is noteworthy to point out that the triplet state energy, as determined at 77 K on the Gd complexes, is about the same for all complexes, 23 450-24 800 cm and therefore there is no correlation between this energy and the quantum yields... 

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