A Versatile Stability-indicating Liquid Chromatographic Method for the Simultaneous Determination of Atenolol, Hydrochlorothiazide and Chlorthalidone

Development of a multivariate model with desirability-based optimization for determination of atenolol and hydrochlorothiazide by eco-friendly HPLC method with fluorescence detection

Determination of a widely used antihypertensive combination of atenolol and hydrochlorothiazide was achieved by rapid and eco-friendly high-performance liquid chromatography method combined with fluorescence detection. The response surface methodology is conducive to the complete separation of the two drugs in a shorter analysis time. The separation of the mixture was achieved using an Inertsil C18 analytical column (150 × 4.6 mm, 5 µ). The mobile phase used was ethanol: potassium dihydrogen phosphate at pH 3 (65:35 v/v) and the flow rate was 0.7 mL/min. The fluorescence detector operated at excitation and emission wavelengths of 230 and 310 nm (atenolol) and 270 and 375 nm (hydrochlorothiazide). The linearity of the developed method covered a concentration of atenolol of 0.05-5 µg/mL and a concentration of hydrochlorothiazide of 0.02-1 µg/mL. The greenness of the developed method was evaluated by analytical eco-scale and the recently reported evaluation method, that is, green analytical procedure index, and it was found to be an excellent, sensitive, and green alternative to the reported methods. The developed method was validated according to the ICH guidelines and compared with the reference method. No significant difference was found in terms of accuracy.

Experimental design optimization of simultaneous enantiomeric separation of atenolol and chlorthalidone binary mixture by high-performance liquid chromatography using polysaccharide-based stationary phases

In this work, enantiomeric separation of a drug combination of two chiral drugs, namely, atenolol and chlorthalidone, is described. Prior investigation of the effect of different variables on the resolution of the enantiomers' peaks and the total run time represented by the retention time of the last eluted peak was conducted using face-centered composite design. Twenty-two experiments were carried out by varying the chiral stationary phase type as a categorical factor and mobile phase composition including the percentage of ethanol and percentage of diethylamine as continuous factors. According to the optimization process, a mobile phase consisting of hexane:ethanol:DEA:TFA (60:40:0.2:0.1%, v/v/v/v) pumped at flow rate 1 ml min^-1 onto Lux-Cellulose 2 stationary phase was applied for the chiral separation and quantification of the drug combination at 230 nm. Application of the developed method to the pharmaceutical formulation of this combination was successfully performed, and satisfactory percentage of recoveries was obtained. The method was also fully validated following International Conference on Harmonization (ICH) guidelines. This method could be of high value and relevance for application in quality control laboratories.