DEVELOPMENT AND VALIDATION OF RP-HPLC METHOD TO DETERMINE URSODEOXYCHOLIC ACID IN PHARMACEUTICAL DOSAGE FORMS

This study describes development and subsequent validation of a reversed phase high performance liquid chromatographic (RP-HPLC) method for the estimation of ursodeoxycholic acid used to solubilize cholesterol gallstones, in conventional tablet dosage formulation and in prepared dosage form. The chromatographic system was achieved in a BDS Hypersil C8 column (Thermo, 250mm x 4.6 mm, 5 µ) with an isocratic mobile phase comprising of methanol, water and phosphoric acid (77:23:0.6 v/v). Since the drug shows moderate absorption only in the short UV wavelength region (200-210 nm), quantification of the amount released from the pharmaceutical preparations by simple UV spectrophotometry is hampered by possible interferences from formulation excipients and dissolution medium components.  A new method has been developed utilizing the above mobile phase and detection in refractive index (RI) detector. In this chromatographic condition ursodeoxycholic acid was eluted about 3.0 min with no interfering peaks of excipients used for the preparation of dosage forms. The method was linear over the range from 240-360 µg/mL in raw drug (r² = 0.995). The intra-day and inter-day precision values were in the range of 0.144 – 0.332 % and 0.166 – 0.292 % respectively. Limit of detection (LOD) and limit of quantitation (LOQ) were 0.6 µg/mL and 2 µg/mL respectively. Results were validated according to International Conference on Harmonization (ICH) guidelines in marketed and prepared tablet formulation. The validated HPLC method is simple, sensitive, precise, accurate and reproducible.