Optimized preparation of oridonin-loaded nanoparticles by central composite design and response surface method

Key words: 
• oridonin /
• nanoparticles /
• modified spontaneous emulsification solvent diffusion method /
• central composite design and response surface method

Abstract: Objective : To optimize the formulation of oridonin-loaded PLA nanoparticles with modified spontaneous emulsification solvent diffusion method. Methods :Applying central composite design and response surface method,choose the concentration of drug in organic phase,the concentration of PLA in organic phase and the ratio of water phase to organic phase as the influence factors.The evaluation parameters included entrapment efficiency,drug loading rate and particle size.Experiments were done on the theory of central composite design.The data were simulated using multi-linear equation and second-order polynomial equation.The possibly optimal formulation was predicted by response surface method. Results : TThe range of the optimal conditions were the concentration of drug in organic phase 0.5～0.8 mg/mL,the concentration of PLA in organic phase 1.6～2.6 mg/mL,the ratio of water phase to organic phase 1～1.5 According to the optimal conditions,the mean particle size,entrapment efficiency and drug loading rate were 98.5 nm,（28.86 ±0.93） % and（8.23 ±0.35） %,respectively. Conclusion :The central composite design and response surface method are useful for the optimization of preparing oridonin-loaded PLA nanoparticles.The established model could predict the parameter of the formulations exactly and properly.