ABSTRACT
AIM To investigate the correlation between surface features and hygroscopicities of Achyranthis bidentatae Radix extract powders added with different excipients.METHODS Achyranthis bidentatae Radix aqueous extract was added with crospovidone CL-SF,maltodextrin DE11-14,β-cyclodextrin,Arabic gum,dextrin,mannitol,soluble starch and lactose,respectively,after which extract powders were prepared,and hygroscopicities and morphological changes were determined.Then the surface features of various extract powders were compared by double exponential model.RESULTS Compared with other excipients,soluble starch and β-cyclodextrin could reduce the saturated moisture content of the extract powders more obviously,and crospovidone CL-SF exhibited the strongest inhibitory effect on powder synechia after moisture absorption.No direct relationship between hygroscopicities and specific surface area or pore volume was observed,but specific surface area,pore volume and average particle size demonstrated positive correlations with model parameter A1.CONCLUSION Addition of proper excipients can improve the surface features and hygroscopicities of Achyranthis bidentatae Radix extract powders.