DEVELOPMENT AND VALIDATION OF IN-VITRO DISSOLUTION STUDIES OF GEMIFLOXACIN MESYLATE AND AMBROXOL HYDROCHLORIDE FROM ITS COMBINED SUSTAIN RELEASE TABLET DOSAGE FORM WITH RESPECT TO ACCELERATED AGING CONDITIONS BY HPLC ASSAY METHODS.

In-vitro dissolution studies for gemifloxacin mesylate and ambroxol hydrochloride from its combined SR tablet dosage form was developed and validated successfully as per ICH guidelines. Dissolution studies were performed using USP Type II apparatus for period of 12 h, first 2 h in 0.1N HCl (Acid stage), then continued in phosphate buffer pH 6.8 (Buffer stage) at 50 RPM. After 10 h both the drugs shows complete dissolution profile. Exposure of tablets to ICH accelerated stability condition 40 0 C ± 2 0 C/75% RH ± 5% for 6 months and photolytic studies in an open dish to light for 30 days, using a combination of cool white and ultraviolet fluorescent lamps in a photostability chamber. Exposure energy was minimum of 1.2 million lux h fluorescent light and 200W h/m 2 UV. Dissolution samples were analyzed by newly developed HPLC method comprising of mobile phase as 0.02M potassium dihydrogen orthophosphate buffer: Acetonitrile (70:30 v/v) with 1% Triethylamine (2 ml/100 ml mobile phase) and its pH adjusted to 5.5 with ortho phosphoric acid and detection was executed on PDA detector at 244 nm. The retention time (RT) of gemifloxacin mesylate and ambroxol hydrochloride was found to be 2.34 ± 0.2 and 4.21 ± 0.2 min respectively. Results of analysis demonstrated that accelerated aging results in rapid increases in tablet hardness, and changes in water content upon storage leads to decrease in dissolution rate. The tablet matrix appears to rapidly absorb atmospheric moisture, as demonstrated by tablet weight W