Objective: To prepare paeonol-loaded polyethylene glycol (PEG)-poly(lactic-co-glycolic acid) (PLGA) nanoparticles modified by chitosan and investigate its in vitro release behavior. Method: Taking PEG-PLGA as carrier material

chitosan as surface modifier

paeonol-loaded PEG-PLGA nanoparticles modified by chitosan was prepared by nano precipitation method

formulation of this preparation was optimized by orthogonal design

characteristics of nanoparticles were evaluated.In vitro release of this preparation was characterized with phosphate buffer (pH 7.4) as medium. Result: After being modified by chitosan

particle size of paeonol-loaded PEG-PLGA nanoparticles increased

while its Zeta potential turned to positive charge

its shape was spherical.Mean particle size

Zeta potential

drug loading efficiency and encapsulation efficiency were (96.6±3.2) nm

(30.61±0.34) mV

10.87% and 79.37%.Accumulated release rate of this nanoparticles reached 62.4% at 24 h. Conclusion: Paeonol-loaded PEG-PLGA nanoparticles modified by chitosan is prepared successfully

which shows a sustained-release characteristics with good in vitro properties.