Chemometric-assisted RP-HPLC method for the simultaneous determination of ambroxol hydrochloride, terbutaline sulfate,and guaiphenesin in combined dosage form

Abstract

An isocratic reverse-phase High performance liquid chromatography (HPLC) method using a chemometric model was developed and validated for the simultaneous determination of ambroxol hydrochloride, terbutaline sulfate, and guaiphenesin in their combined dosage form. Central composite design which is a subset of response surface methodology was used as the chemometric model. The separation of three drugs was carried out by using a Phenomenex C18 column and detection at 220 nm using a UV detector. Based on initial trials, the three factors selected for the design were methanol (MN) concentration, mobile phase pH, and flow rate in the range of 55%-65% (v/v), 4-5 units, and 0.6-1 ml/min, respectively. The impact of the selected factors on the responses like retention time of first peak (tR1), resolution of 2nd and 3rd peak (Rs2,3), and theoretical plates of the first peak (TP1) were evaluated. Derringers' desirability function was used to optimize the responses. The conditions which were optimized for the assay of drugs were MN, ACN, and 50 mM KH2PO4 (pH 5) in the ratio of 55:10:35 at a flow rate of 0.8 ml/minute. The developed and optimized method was validated as per the International conference on harmonization (ICH) guidelines and can be used for routine analysis in quality control laboratories.