4. Conclusions
The potential for using aqueous micellar medium for FIA
titrations of phenothiazine derivatives was tested. A comparison
was made of the experimental arrangement with the
mixing gradient chamber and in the high-speed mode, in both
cases, with potentiometric and spectrophotometric detection.
It was found that, in both cases, FIA titration with the mixing
gradient chamber is more sensitive; however, it has the
disadvantage of a low sampling frequency. A possible explanation
of the discrepancy between the results obtained and
the literature data, according to which FIA high-speed titrations
should be more sensitive than titrations with a mixing
gradient chamber, could probably lie in the kinetic effects
occurring in the micellar medium (the reaction time for highspeed
titrations is not sufficient for establishing equilibrium
on the surface of the micelles). In comparison of the two
types of detection, the spectrophotometric detection enables
work in a lower concentration range than potentiometric one,
which is suitable for higher analyte concentrations.