Microwave-assisted drying of Prasakanphlu herbal granules and formulation development of Prasakanphlu tablets: Design of Experiments approach

This work aimed to apply the Design of Experiments (DOE) approach in microwave-assisted drying of Prasakanphlu (PSKP) herbal granules. Furthermore, DOE was applied in the formulation development of PSKP tablets. The 3² full factorial design consisted of two factors (i.e., microwave power and microwave time) and two responses (i.e., moisture content and eugenol content) that were used for optimized microwave-assisted drying of PSKP granules. The optimal condition was microwave power of 300 W for 15 min. This condition was used to dry the wet granules of PSKP for optimization of tablet formulation. The Box–Behnken design was applied in the formulation development of PSKP tablets; three factors (i.e., compression force, amount of polyvinyl pyrrolidone K30, and amount of sodium starch glycolate) and four responses (i.e., tablet thickness, hardness, friability, and disintegration time) were included in the design. Results showed that the optimal parameters were compression force of 1500 psi, 4.5% polyvinyl pyrrolidone K30, and 2% sodium starch glycolate. Furthermore, rapid dissolution of the optimal tablets was found. In conclusion, the work succeeded in applying DOE for PSKP granule drying by microwave and formulation development of PSKP tablets with desired properties.

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