Polarization immunoassay theophylline

Tibi, L. and Burnett, D., Interference by caffeine in polarization immunoassays for theophylline, Ann. Clin. Biochem., 291 1994. 

Figure 6.1. Fluorescence polarization immunoassay for theophylline. (A) Effect of theophylline rabbit antiserum ( ) and normal rabbit serum (A) on the fluorescence polarization of the theophylline-umbelliferone conjugate. (B) Fluorescence polarization of the theophylline-umbelliferone conjugate in the presence of varying concentrations of theophylline. (Reprinted from Ref. 1, with permission from Academic Press.)...

Niemann, A., Oellerich, M., Schumann, G., Sybrecht, G.W. (1985). Determination of theophylline in saliva, using fluorescence polarization immunoassay (FPIA). J. Clin. Chem. Clin. Biochem., 23(11), 725-732. 

Li TM, Benovic JL, Burd JF. Serum theophylline determination by fluorescence polarization immunoassay utilizing an umbelliferone derivative as a fluorescent label. Anal Biochem 1981 118 102-7. 

The determination of theophylline in plasma can also be accomplished by various immunoassay techniques.66-67 Theophylline was also determined by a polarization fluoroimmunoassays but found to have a caffeine interference.88. In a more research oriented application, the interaction of caffeine with L-tryptophan was studied using h NMR with the results indicating that caffeine interacted with tryptophan in a 1 1 molar ratio through parallel stacking.69... 

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