Research of Tianning Dropping Pills Preparation by Response Surface Methodology Optimization Model

OBJECTIVE To optimize the formulations of compound Tianning dropping pills by central composite design- response surface methodology. METHODS Dropping pill was prepared through melting method with PEG6000 and S40 as combined carrier. Independent variables were drugs content and PEG6000 content, while dependent variables were weight variation of pills and the ferulic acid dissolution rate of definite time. Software was used to fit multivariate linear equation and second-order polynomial equation for experimental data. Response surface and contour plot were delineated according to bestfit mathematic models by software, and the optimum formulation was selected by response surface. RESULTS Quadratic multinomial model was better than multivariate linear model, and the regression coefficient was 0.970. The best prescription of compound Tianning dropping pill was that drugs content was 23%, while PEG6000 content was 45%. The bias between the observed and predicted values of the optimum process was negligible, indicating the high predictability of the model. CONCLUSION The model established by central composite design-response surface methodology and SPSS software is accurate for prediction and can be used to optimize the preparation process of Tianning dropping pills.