Optimization of central composite design for the preparation process and in vitro evaluation of Prunella vulgaris dropping pills solid dispersion

Key Points

• The aim is to optimize the preparation process of dropping pills made from Prunella vulgaris extract using solid dispersion techniques.
• Utilized ultrasound-assisted solvent extraction for flavonoid extraction.
• Prepared solid dispersions using the solvent-melt method.
• Applied central composite design-response surface methodology to optimize preparation parameters like drop distance and liquid temperature.
• Evaluated preparation parameters through comprehensive scoring and in vitro dissolution tests.
• Conducted pharmacokinetic studies in rabbits to assess bioavailability.
• Optimized parameters achieved include a dropper diameter of 2.5mm and a drop rate of 20 drops/min.
• Cumulative dissolution rate within 45 minutes reached 89% to 92% with an overall desirability (OD) value of 0.88 to 0.92.
• Pharmacokinetic analysis showed significant improvements in Cmax and AUC for solid dispersions compared to traditional extracts.