Validation of an HPLC method for the quantification of ambroxol hydrochloride and benzoic acid in a syrup as pharmaceutical form stress test for stability evaluation

A method is described for ambroxol, trans-4-(2-amino-3,5-dibromobenzylamino cyclohexanol hydrochloride, and benzoic acid separation by HPLC with UV de tection at 247 nm in a syrup as pharmaceutical presentation. Optimal condit ions were: Column Symmetry Shield RPC8, 5 mum 250 x 4.6 mm, and methanol/(H 3PO4 8.5 mM/triethylamine pH = 2.8) 40:60 v/v. Validation was performed usi ng standards and the pharmaceutical preparation which contains the compound s described above. Results from both standards and samples show suitable va lidation parameters. The pharmaceutical grade substances were tested by fac tors that could influence the chemical stability. These reaction mixtures w ere analysed to evaluate the capability of the method to separate degradati on products. Degradation products did not interfere with the determination of the substances tested by the assay. (C) 2001 Elsevier Science B.V. All r ights reserved.