Objective To investigate the different effects of carboxymethyl starch sodium (CMS) and polyvinylpyrrolidone (PVPP) on the structure, free surface energy, and key direct compression properties of composite particles produced by co-spray drying based on traditional Chinese medicines (TCM) extracts. Methods This study selected extracts of Fuling (Poria), Danggui (Angelicae Sinensis Radix), Huangqi (Astragali Radix), Danshen (Salviae Miltiorrhizae Radix et Rhizoma), and Jinyinhua (Lonicerae Japonicae Flos) (PC、AS、AM、SM、LJ) as model drugs, and CMS and PVPP as modifiers. The composite particles of TCM extracts (CP-PC/AS/AM/SM/LJ-CMS and CP-PC/AS/AM/SM/LJ-PVPP) were prepared via co-spray drying. The properties of the co-spray dring liquid, and structure, free surface energy and direct compression properties of composite particles were comprehensively characterized. The different effects of CMS and PVPP on these properties were analyzed by statistical analysis. Results The application of different modifiers led to differential variations in the properties of the co-spray dring liquid, as well as in the structural characteristics, free surface energy, and direct compression properties of the composite particles. Compared to PVPP, co-spray dried liquid containing CMS exhibited increased solid content and viscosity, and lower surface tension and hydrodynamic size (except for CP-SM/LJ-CMS); All composite particles exhibited spherical structures, and those containing CMS showed smoother surfaces and larger particle size than those containing PVPP; The composite particles containing CMS brightness values (except for CP-AM-CMS), hardness (except for CP-AS/AM-CMS), elasticity, and rebound property (except for CP-AS/AM-CMS) were lower; The cohesion (except for CP-PC/LJ-CMS), cohesion work (except for CP-SM/LJ-CMS), free surface energy (except for CP-SM/LJ-CMS), and polarity index (except for CP-SM -CMS) of composite particles containing CMS were relatively high; The Carr’s index, Hausner ratio, angle of repose (except for CP-SM-CMS), and disintegration time (except for CP-LJ-CMS) of composite particles containing CMS were all smaller, while composite particles containing PVPP demonstrated higher tensile strength. Conclusion The properties of TCM extract co-spray drying solutions, structures, free surface energy, and direct compression performance of composite particles containing CMS and PVPP were exhibited different effects. These findings provide valuable insights for advancing co-spray drying technology in TCM extracts and for preparing composite particles suitable for direct powder compression.

co-spray drying  /  composite particles  /  carboxymethyl starch sodium  /  polyvinylpyrrolidone  /  structure  /  free surface energy  /  direct compression of powder