Objective: To optimize the formulation of ligustrazine phosphate thermosensitive gel by the central composite design-response surface methodology (RSM plus CCD).
Methods: In the formulation design using RSM plus CCD, independent variables were the amounts of poloxamer 407 and poloxamer 188, and gel temperature was dependent variable. Multilinear and quadratic models were used to estimate the relationship between the dependent and the independent variables, select the optimal formulations and validate.
Results: The quantitative relationships between two factors and evaluation index were characterized, quadratic model had better prediction capability than multilinear model.
Conclusion: Quadratic model is performed in the optimization of formulation due to the statistical confidence. The optimization of ligustrazine phosphate thermosensitive gel formulation can be achieved by the central composite design and response surface methodology.