ABSTRACT
OBJECTIVE： To prepare Ursolic acid （UA）/Pluronic F127 （PF127）/TPGS-doxorubicin （DOX） mixed nanomicelles， and to characterize it and study its in vitro release behavior. METHODS： UA/PF127/TPGS nanomicelles were prepared by thin film hydration method. Using encapsulation efficiency of UA as index， combined with the results of single factor tests， L9（34） orthogonal test was used to optimize drug dosage of UA， molar ratio of PF127 to TPGS， hydration temperature and hydration volume， validation test was performed. On the basis of succinylated TPGS， TPGS-DOX was synthesized and mixed with UA/PF127/TPGS to prepare UA/PF127/TPGS-DOX mixed nanomicelles， the appearance， particle size and critical micelle concentration （PF127/TPGS） were investigated. The drug release behavior was examined by dialysis bag diffusion method. RESULTS： The optimal preparation technology of UA/PF127/TPGS nanomicelles was as follows as drug dosage of UA 8 mg， molar ratio of PF127 to TPGS 3 ∶ 7， hydration temperature 50 ℃， hydration volume 4 mL. Average encapsulation efficiency of UA in nanomicelles was 89.00％ （RSD＝0.43％， n＝3）. The prepared UA/PF127/TPGS-DOX mixed nanomicelles solution was clear with opalescence. The nanomicelles were spherical and uniform in size； average particle size was （115.00±9.42） nm； critical micelle concentration of PF127/TPGS （molecular ratio 3 ∶ 7） was 0.001 3％. The in vitro drug release of UA and DOX in the mixed nanomicelles was significantly slowed down， compared with raw materials or substance control. The drug release process of the two drugs in the nanomicelles conformed to Weibull equation. CONCLUSIONS： UA/PF127/TPGS-DOX mixed nanomicelles are successfully prepared with uniform particle size， good stability and good sustained-release effect.
ABSTRACT
OBJECTIVE： To optimize the preparation technology of Celastrol nanostructured lipid carriers （Cel-NLC）， and to characterize it. METHODS： Cel-NLC was prepared by melt-emulsification ultrasonic method. Based on single factor test， using encapsulation rate of Cel as index， the ratio of liquid lipid （the ratio of total mass）， the amount of compound emulsifier and the dose of main drug were optimized by central composite design-response surface methodology. Validation test was conducted. Zeta potential and particle size of Cel-NLC that prepared by optimal prescription were determined by using granularity and Zeta potential analyzer. The morphology of liposome was observed by TEM. RESULTS： The optimal prescription included that the ratio of liquid lipid was 39％；the amount of compound emulsifier was 196 mg；the dose of main drug was 8 mg. The average encapsulation efficiency of 3 batches of Cel-NLC was 87.22％； average particle size was （41.2±1.1） nm，and average Zeta potential was （－18.4±0.2） mV （n＝3）. It was spherical under electron microscopy. CONCLUSIONS： The optimized technology is simple， stable and feasible， and it is suitable for the preparation of Cel-NLC.