Development and Validation of Stability-indicating RP-HPLC Method for The Estimation of Pseudoephedrine, Ambroxol and Desloratadine in Bulk and Their Tablet Dosage Forms

Abstract

A simple, accurate, selective and stability-indicating RP-HPLC method was developed for the simultaneous estimation of pseudoephedrine, ambroxol and desloratadine in bulk and their tablet formulations. Effective chromatographic separations were achieved on a Hypersil BDS C8, 250×4.6 mm, 5 µ column with reverse phase elution. The mobile phase composed of 0.01 M potassium dihydrogen phosphate and acetonitrile in the ratio of 50:50 v/v at a flow rate of 1.0 ml/min. The detection was carried out at 220 nm. The retention times were 2.2 min for pseudoephedrine, 3.4 min for ambroxol and 5.5 min for desloratadine. The linearity ranges for pseudoephedrine, ambroxol and desloratadine were 15 to 90 µg/ml, 30 to 180 µg/ml and 2.5 to 15 µg/ml, respectively with correlation coefficient 0.999. The developed method was validated statistically with respect to linearity, range, precision, accuracy, specificity, robustness, ruggedness, detection and quantification limits and also subjected to stress conditions like acidic and alkaline hydrolysis, oxidation, photolysis and thermal degradation. The method was accurate, precise, specific, rapid and found to be suitable for the analysis of commercial samples. Pseudoephedrine hydrochloride (PSD) is (1S,2S)-2-methylamino-1-phenylpropan-1-ol hydrochloride and official in European Pharmacopoeia and U.S. Pharmacopoeia. Ambroxol hydrochloride (AMB) is trans-4-[(2-amino-3,5-dibromobenzyl)amino] cyclohexanol hydrochloride and official in British Pharmacopoeia. Desloratadine (DLT) is 8-chloro-6,11-dihydro-11-(4-piperdinylidene)-5H-benzo[5,6] cyclohepta[1,2-b] pyridine is non pharmacopeial drug. Fig. 1 shows chemical structures of three analytes. The three drug combination in the ratio of 30:60:5 mg PSD, AMB and DLT, respectively in tablet dosage form is available under the brand name Nucope-AD. A few methods have been reported individually or in combination with other drugs including simultaneous estimation of AMB and loratadine by spectrophotometric method [1] , high performance liquid chromatographic (HPLC) method [2-3] , simultaneous estimation of AMB and DLT by spectrophotometric method [4-6] , HPLC [7,8] , HPTLC [9]. Since no methods were reported for the simultaneous estimation of PSD, AMB and DLT in bulk and pharmaceutical dosage forms, an attempt was made to develop a simple, accurate, precise and rugged method was developed for the estimation of these drugs simultaneously in bulk and tablet formulations. MATERIALS AND METHODS HPLC grade acetonitrile, potassium dihydrogen phosphate AR Grade and potassium hydroxide AR grade were purchased from SD Fine-Chem, Mumbai, India were used in the study. Reference samples were obtained from M/s. Richer Pharmaceuticals, Hyderabad, India.