Europium fluorescence

Homogeneous TR-FIAs have been reported in which proprietary lanthanide chelates are used. In a homogeneous immunoassay for T4, a fluorescent europium chelate coupled to thyroxine is quenched by antibody binding. 90 A similar approach is used for estrone-3-glucuronide. 91 TRFIAs based on homogeneous methods have not yet become widely used. 

Ye ZQ, Tan MQ, Wang GL, Yuan JL (2004) Novel fluorescent europium chelate-doped silica nanoparticles preparation, characterization and time-resolved fluorometric application. J Mater Chem 14 851-856... 

Wu M, Lin Z, Durkop A, Wolfbeis OS. Time-resolved enzymatic determination of glucose using a fluorescent europium probe for hydrogen peroxide. Analytical and Bioanalytical Chemistry 2004, 380, 619-626. 

Tan MQ, Wang GL, Hai XD et al (2004) Development of functionalized fluorescent europium nanoparticles for biolabeling and time-resolved fluorometric applications. J Mater Chem 14 2896-2901... 

Fig. 3 Emission spectra of a fluorescent europium chelate with two different delay times, (a) using a delay of 2 ps showing also Di emission, (b) with a delay of 7 ps whereafter only the long decay Do emissions are visible...

Sevens L., M. Vaisala, I. Hemmila, H. Kojola, G. M. Roomans, E. Soini. Use of Fluorescent Europium Chelates As Labels in Microscopy Allows Glutaraldehyde Fixation and Permanent Mounting and Leads to Reduced Autofluorescence and Good Long-Term Stability, Microsc. Res. Techn., 28, 149-154 (1994). 

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