Reverse Phase Liquid Chromatographic Method for the Quantification of Di-P-Toluoyl-D-Tartaric Acid in Escitalopram Oxalate Drug Substance

Abstract

A simple and rapid high performance liquid chromatographic method has been established to quantify
the optically active precipitant Di-p-Toluoyl-d-Tartaric acid (DPTTA) at very low level in
Escitalopram oxalate drug substance. The method is subsequently validated to prove its suitability,
sensitivity and repeatability. The high performance liquid chromatographic (HPLC) method is
developed in such a way that to enhances the detection level and minimizes acquisition time by using
suitable buffer of 0.02% (v/v) of Orthophosphoric acid pH 3.0±0.5 and Acetonitrile as eluent in
isocratic mode. The retention time of DPTTA is about 4.0 min and the total acquisition time was less
than 15 min. The optimized method was validated to prove its performance characteristics by
demonstrating selectivity, sensitivity (limit of detection and quantification), linearity, precision and
accuracy. The experimentally established limit of detection and quantification was found to be 0.040
µg mL-1
and 0.120 µg mL-1 respectively and the overall percent accuracy (recovery) of the samples
evaluated at different concentration levels was found to be 99.0, indicating the sensitivity and accuracy
of this optimized HPLC method by citing the guideline requirement.