Background: Tolterodine was quantitatively determined using variable analytical methods
including; spectrophotometric and chromatographic methods. Spectrophotometric methods are usually
fast, easy to handle, cost effective and very reliable for the routine assay during in process quality control
procedures. Eosin Y has been used to determine several basic compounds through the formation of
colored complexes. In this research work, spectrophotometric method is developed to determine Tolterodine
in bulk and in tablet via ion pair complex with Eosin as complexing agent.
Methods: The method developed in this work was based on the formation of a colored binary complex
between the tertiary amine group in (TOL) molecule and the hydroxyl group in Eosin Y molecule. The
absorbance of the chloroform extractable complex was measured at 530 nm using spectrophotometric
Result: The method obeyed Beers Lambert law and the linearity range was 18.6 -58.2 µg mL-1. The
calibration curve equation is Y=9.28X + 0.07 with a linear regression of 0.992. The method was applied
for the assay of (TOL) in commercially available tablets.
Conclusion: Sensitive, specific, accurate and cost effective analytical method was developed in this
work. It was found that the method could be used for a quick assay of the Tolterodine tartrate in bulk
and in pharmaceutical dosage form for research and quality control purposes.