Formulation Optimization of “Three-Six-Nine” Ointment by Box-Behnken Response Surface Method

OBJECTIVE To optimize the extraction process of volatile oil components in “Three-Six-Nine” ointment to prepare the “Three-Six-Nine” sustained-release gel paste. METHODS The Box-Behnken response surface method was used to optimize the extraction process of the volatile oil of the “Three-Six-Nine” ointment. The receiving rate of the volatile oil was taken as the evaluation indicator, and the particle size of raw material, extraction temperature and extraction time were taken as the investigation factors. The binomial equation was used to fit the experimental results to verify the optimal extraction conditions. The nano-lipid drug delivery system based on β-cyclodextrin was prepared by emulsification ultrasound-rotary evaporation method. The quality evaluation criteria were sensory evaluation, formativity measurement, skin followability, cold resistance evaluation and heat resistance evaluation. RESULTS The best extraction process of the volatile oil of “Three-Six-Nine” ointment was as follows: raw material particle size over 40 mesh screen, with extraction time of 3 h and extraction temperature of 50 ℃. The amount of volatile oil extracted was (0.469±0.021)mL, the yield of volatile oil was (1.78±0.08)mL·g^-1. The results implied “Three-Six-Nine” ointment shown stable formability, heat and cold resistance, and had good adhesion and skin adhesion. CONCLUSION Box-Behnken response surface optimization method is simple and predictable, the prepared “Three-Six-Nine” gel paste has good quality.