Analytical Quality by Design Approach in Selection of Method Variables for Simultaneous Analysis of Ciprofloxacin and Hydrocortisone by LC Method Using Taguchi Method

Abstract

With reference to the importance of quality by design approach in regulatory flexibility and with an unreliable retention behavior of both ciprofloxacin and hydrocortisone on reversed phase column, Taguchi method was employed in selection of method variables, to develop liquid chromatographic (LC) method for simultaneous analysis. Taguchi method was used as tool in analytical quality by design (AQbD) approach at screening stage of robust and cost effective method development. There were five input method variables viz. type of organic phase (X1), Buffer (X2), type of column (X3), flow rate (X4) and pH (X5) investigated against the method responses like retention times (Y1 and Y2), theoretical plates (Y3 and Y4) and resolution (Y5), respectively for hydrocortisone and ciprofloxacin. Results were analyzed statistically by licensed Sigma Tech software and the obtained values of coefficients and % of sum of squares for each response were interpreted. The conclusion was arrived based on the statistical analysis for the selection of acetonitrile, C18 column, 0.25 % TEA (pH adjusted) as buffer, while flow rate and pH of mobile phase are controlled. Further, the selected method variables were used for method optimization and then verified for method performances as required by ICHQ2 guidelines.