Comparative in vitro assessment of tolterodine tartrate tablets by high performance liquid chromatographic (HPLC)

Tolterodine tartrate, (R)-N,N-diisopropyl-3(2-hydroxy5-methylphenyl)-3-phenylpropanamine l-hydrogen tartrate (Fig. 1), is a new, potent and competitive muscarinic receptor antagonist in clinical development for the treatment of urge incontinence and other symptoms of unstable bladder (1-3). Tolterodine has a high affinity and specificity for muscarinic receptors in vitro and exhibits the selectivity for the urinary bladder over salivary glands in vivo, so it has the advantageous tolerability profile in terms of the low frequency of bothersome dry mouth (4). After oral administration, tolterodine is metabolized in liver, resulting in the formation of the 5-hydroxymethyl derivative, a major pharmacologically active metabolite (5). However, a small proportion Abstract Tolterodine tartrate, is a new, potent and competitive muscarinic receptor antagonist in clinical development for the treatment of urge incontinence and other symptoms of unstable bladder. The purpose of this study is to establish a reliable and quick method for the assignment of tolterodine tartrate by high performance liquid chromatography with ultraviolet detection (HPLC-UV). A rapid and sensitive high performance liquid chromatographic (HPLC) method has been developed for determination of tolterodine tartrate. Mobile phase was composed of phosphate acetate 0.1 M (pH 2.5)-acetonitrile (50:50 v/v) with a flow rate of 1.2 ml/min. The eluted peaks were detected by a UV detector was set at wavelength of 285 nm. The method was validated in the range of tolterodine tartrate concentrations from 10 to 100 μg/ml. The limits of detection (LOD) and quantitation (LOQ) of the method were 5 and 10 μg/ml, respectively. The average drug recovery was 98.20 % throughout the linear concentration range. The average within-run and between-run accuracy values of 98.56 % and 99.11 % respectively. Statistical assessment of various in vitro dissolution parameters and assay results was also conducted to establish if there were any significant difference among them. The validated HPLC method has been used successfully to study tolterodine tartrate.