OBJECTIVETo prepare a novel floating micropellets containing hydroxy propyl-beta-oyclodextrin(puerarin-HP-beta-CD) for gastroretentive dosage form and evaluate its pharmaceutical characteristics in vitro.

METHODThe puerarin HP-beta-cyclodextrin inclusion complex was prepared by freeze-drying method. Puerarin and its HP-beta-CD inclusion complex were incorporated into alginate beads, respectively. The effect of methyl cellulose (MC), Mg-Stearate and chitosan on buoyancy and cumulative release rate of puerarin were investigated in simulated gastric fluid.

RESULTThe spectrums of FTIR and profiles of X-ray powder diffraction of samples proved the formation of inclusion complex between puerarin and HP-beta-CD. Magnesium stearate had a significant effect on the buoyancy of micropellets, and satisfied results were gained by the content with 2%. The solubility of puerarin was increased 65.6-fold by the formation of inclusion complex, the dissolution rate and cumulative release percentage also improved significantly although with the burst release phenomena. The micropellets showed sustained release properties by using puerarin-HP-beta-CD inclusion complex mixed with puerarin (1:1) and treated thoroughly under homogenizer.

CONCLUSIONThe solubility and release rate of puerarin are increased by the formation of inclusion complex with HP-beta-CD and its gastroretentive dosage forms displayed satisfied floating and sustained release characteristics.