Process Optimization and Powder Performance Evaluation of Chitosan/Attapulgite Compound Excipients for Curing Peppermint Volatile Oil

OBJECTIVE To prepare a compound excipient suitable for curing peppermint oil using chitosan(CS) and attapulgite(ATP) as raw materials. METHODS CS and ATP were dispersed with 3% glacial acetic acid as dispersion medium, peppermint oil was used as a model drug, the retention rate of peppermint oil was the inspection index, the modification ratio of the composite excipients, the stirring time and the stirring temperature were the investigation factors, the best process parameters of CS/ATP composite excipients for curing peppermint oil was optimized by response surface methodology, and the powder properties of the composite excipients and the moisture and thermal stability after curing the volatile oil under the process conditions were tested, and scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction characterization analysis was performed at the same time. RESULTS The best process parameters for the composite excipient CS/ATP to solidify the volatile oil of mint were: the ratio of CS to ATP was 1∶9, the stirring time was 16 h, and the stirring temperature was 55 ℃. Under the optimal conditions for the preparation of CS/ATP composite excipients, it was placed at 50 ℃ after 3 d, the retention rate of the oil of peppermint was 78.02%, which was 90.45% higher than the retention rate of the oil of peppermint which was not cured with CS/ATP under the same conditions. The powder performance test of CS/ATP composite excipients showed that the composite excipients had better moisture barrier properties and good liquidity. CONCLUSION The preparation process of CS/ATP composite excipients is simple and has strong operability. It has potential application value in curing peppermint oil.