A new, simple, specific and economic UV Spectrophotometric method and HPLC method for the estimation of Dofetilide content in bulk and laboratory prepared mixture. UV spectrophotometric detection was carried out at absorption maxima (λmax) at 231nm using methanol as a solvent. The quantitation of drug was carried out using A1% 1cm at 231nm and Beer’s law was obeyed in the concentration range of 2.5-20 μg/ml, with correlation coefficient value less than 1.The chromatographic separation was carried on a C-18 (250 mm × 4.6 mm, 5μ) column using an isocratic mode with a mixture of Acetonitrile:Phosphate Buffer (pH-7) in the ratio of 55:45% v/v as a mobile phase. The flow rate was 1.5ml/min, temperature is maintained at ambient and detection was made at 231 nm using Photodiode array (PDA) detector. The developed method was validated according to ICH guidelines and different analytical parameters such as linearity, precision, accuracy, specificity, limit of detection, limit of quantitation were determined. The percent amount of drug estimated was nearly 100%, found to be a good agreement with label claim of prepared laboratory mixture. The proposed method was validated for its accuracy, precision, robustness, ruggedness, linearity, limit of detection, limit of quantitation and was found to be in range (% RSD<2.0 and SD <±2.0). Both methods were validated and found to be simple, sensitive, accurate, and precise. The results of the study and statistical data proved the applicability of the present method in routine analysis of Dofetilide in bulk as well as laboratory prepared mixture.

The aim of present study was to develop and validate a dissolution test method for Cyclobenzaprine HCL in its formulation using RP-HPLC method. Design: Optimization of chromatographic parameters, development of the dissolution test method using RP-HPLC and to validate the developed methods as per ICH guidelines. Materials and Methods: The optimized dissolution parameters includes USP apparatus II at a paddle rotation rate of 50 rpm and 900 ml of 1.2 pH 0.1N HCL buffer at 37 • C±0.5 • C. Under these conditions, the in vitro release profiles of cyclobenzaprine HCL showed good results. The drug release was estimated by RP-HPLC using column Shodex C 18-4E (250×4.6mm×5µm), detection wavelength 289.4 nm having the flow rate 1.0 mL/min using Acetonitrile : phosphate buffer (3.0 pH) in the proportion of 65:35% v/v. Results: The percent drug amount released estimated by proposed method was found to be 99.04%, The method was found to be linear with correlation coefficient was found to be 0.9991 in the concentration range was 2-10 µg/mL. The mean % recovery of Cyclobenzaprine was found to be 100.04.Precision values observed less than 2. All the validation parameters were within the acceptance range. Conclusion: The results obtained by proposed dissolution method for tablet formulation containing Cyclobenzaprine HCL are reliable, precise and accurate. Hence it was routinely adopted for dissolution analysis of the said drugs in the formulation.