Introduction:
In the pharmaceutical industry, the development of pediatric oral powders has been gaining popularity due to their ease of administration to young children. Such powders contain various active ingredients including potassium guaiacolsulfonate and sodium benzoate, which are used to treat respiratory diseases. However, the simultaneous determination of these two ingredients using conventional analytical methods is often challenging due to their similar physicochemical properties. Vendors looking for an alternative method to test for these compounds in pediatric oral powders can rely on high-performance liquid chromatography (HPLC). This article presents a novel HPLC method that was developed and validated for the simultaneous determination of potassium guaiacolsulfonate and sodium benzoate in pediatric oral powder.
HPLC Method Development:
To determine the optimal separation and detection conditions for potassium guaiacolsulfonate and sodium benzoate, various chromatographic parameters were evaluated. The best chromatographic separation was achieved using a C8 column, and the mobile phase was composed of methanol and 0.02 M solution of tetrabutylammonium sulfate. The gradient program comprised an initial hold time of 7 minutes with methanol content maintained at 20% (v/v), followed by a linear gradient in 5.5 minutes in which methanol content was increased from 20% (v/v) to 50% (v/v), and a final hold time of 2.5 minutes with methanol content maintained at 20% (v/v). The total flow rate of mobile phase was maintained at 1.0 mL per minute, and the UV detection was performed at 280 nm. The injection volume was set at 20 µl.
Method Validation:
The method was fully validated in terms of specificity, linearity, precision, accuracy, and robustness according to current guidelines. The specificity of the method was demonstrated by the resolution factor (Rs > 2) obtained between the two analytes. Linearity was assessed by analyzing the calibration curve in the range of 10-200 µg/mL for each analyte. The correlation coefficient (R2) was found to be greater than 0.99, indicating a good linearity. The precision of the method was evaluated by analyzing replicate injections of the sample solution. The relative standard deviation (RSD) for intra-day and inter-day precision was less than 2%, demonstrating good precision. The accuracy of the method was determined by analyzing the recovery of the analytes at three different concentration levels. The percentage recovery was found to be within the range of 98-102%, indicating good accuracy. Finally, the robustness of the method was evaluated by analyzing the effect of small changes in mobile phase composition and flow rate on the separation and detection of the analytes. The results indicated that minor changes did not significantly affect the separation and detection of the analytes.
Conclusion:
The developed and validated HPLC method is reliable and suitable for the simultaneous determination of potassium guaiacolsulfonate and sodium benzoate in pediatric oral powders. The method is sensitive, specific, and precise, and provides accurate results. This method provides an alternative to conventional analytical methods and can be used for routine analysis of pediatric oral powders containing potassium guaiacolsulfonate and sodium benzoate.
Keywords: Sodium, HPLC, Assay of potassium guaiacolsulfonate and sodium benzoate.