SIMULTANEOUS ESTIMATION OF LOPERAMIDE HYDROCHLORIDE AND TINIDAZOLE IN BULK AND FORMULATIONS BY REVERSE PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

Abstract

Objective: A new, rapid, selective, precise, accurate and economical, isocratic, reverse phase high-performance liquid chromatography method has been developed for simultaneous estimation of loperamide hydrochloride and tinidazole in bulk and in tablet formulations.

Methods: The separation was achieved by using Lithosphere RP C-18, (250 x 4.6 mm, 5 µm) end capped column with a mobile phase containing sodium-1-octane sulfonate buffer: methanol: acetonitrile (40:30:30%v/v/v) pH adjusted to 4.0 (using dilute orthophosphoric acid). The flow rate was 1.0 ml/m and column effluent was monitored at 224 nm. The method was validated as per international conference on chemical harmonization (ICH) guidelines.

Results: Tinidazole and loperamide hydrochloride were eluted at about 3.1 and 5.4 min respectively, indicating the shorter analysis time. The proposed method was found to be accurate, precise and reproducible. The linearity was established in the concentration range of 10-50 µg/ml. Limit of detection (LOD) and Limit of quantification (LOQ) was found to be 0.001 µg/ml and 0.003 µg/ml for loperamide hydrochloride and 0.01 µg/ml and 0.03 µg/ml for tinidazole.

Conclusion: This method can be used for routine analysis of formulations containing any of the above drugs or combinations without any alteration in the chromatographic conditions.