P. Izquierdo et al., STUDY OF THE EU(III)-TETRACYCLINE-THENOYLTRIFLUOROACETONE SYSTEM BY USING THE STOPPED-FLOW MIXING TECHNIQUE - DETERMINATION OF TETRACYCLINEIN SERUM, Analytica chimica acta, 292(1-2), 1994, pp. 133-139
The enhancing effect of thenoyltrifluoroacetone on the fluorescence in
tensity of the Eu(III)-tetracycline system in the presence of Triton X
-100 was studied by using equilibrium and kinetic measurements. This l
igand significantly improves the sensitivity of equilibrium methods fo
r tetracycline determination based on energy-transfer processes. Kinet
ic methodology implemented by means of the stopped-flow mixing techniq
ue allows analytical data to be acquired within 5 s after the reactant
s are mixed, thereby minimizing manipulation and enabling ready applic
ation of the proposed method to routin analysis for tetracycline in se
rum samples. The calibration graphy was linear over the range 20-1000
ng ml(-1), but can be expanded up to 10000 ng ml(-1) by increasing the
reagent concentrations. The within- and between-assay relative standa
rd deviations were close to 1%. The mean recovery obtained in the anal
ysis of serum samples was 98.8%.