Objective: To prepare sustained release pellets of total tanshitones and optimize its formulation technology. Method: Drug-loaded pellets core was prepared by solid dispersion solubilization technology and fluidized bed technology

this pellets core was coated with Eudragit NE30D

single factor test was used to investigate effect of coating weight

type and dosage of porogen

anti-adhesive agent

curing time and temperature on coating technology. Result: Optimum coating technology was as following:coating weight of Eudragit NE30 5%

with 20% lactose as porogen

50% talcum powder as anti-adhesive agent

curing time 12 h

curing temperature 40 ℃.Coated pellets had good sustained release effect

in vitro release of this drug was in line with First-order release equation. Conclusion: Fluidized bed irrigation method and fluidized bed coating method could be adopted to prepare sustained release pellets of total tanshinones from Salvia miltiorrhiza with slow and stable in vitro release.