RESUMO
Objective To investigate the film coating process of Xianqu Tablets based on the concept of quality by design (QbD), and improve the coating efficiency and stability. Methods Using the QbD as an experimental guidance and the Design-Expert software as a tool, the critical quality attributes affecting Xianqu film coating targets were first determined as the response values, and the process parameters of influencing critical quality attributes were selected as the key factors. Then the Box- Behnken design was used to optimize the process parameters and establish a control space. Finally, the design space were verified by measuring the hygroscopicity of Xianqu Tablets. Results The results showed that the design space was optimized to reduce the actual error by 95% confidence interval, the best range of process parameters were obtained as follow: bed temperature 37-43 ℃, coating solution concentration 9%-11%, coating weight gain 4%-5%. After the Xianqu Tablets were coated under the given conditions, the hygroscopicity of Xianqu Tablets, which had a smooth surface and uniform color, was significantly reduced. Conclusion The desired effects by using a reasonable experimental design concept of QbD were efficiently achieved, it provides a predictive model for the film coating process of Xianqu Tablets through constructing reasonable design space, which not only enhances the flexibility and applicability of the coating process, but also ensures the stable product quality.