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Objective: To prepare curcumin-micelles adopting vitamin E-TPGS (VE-TPGS) and Solutol HS15 (SHS15) as carriers, and study the effect on solubility and oral bioavailability of curcumin (Cur). Methods: Cur was loaded into micelles between VE-TPGS and SHS15 by thin film dispersion method. Particle size, loading efficiency, entrapment efficiency, and in vitro release were carried on to estimate the influence of micelles on Cur; Moreover, oral bioavailability in rats was also evaluated. Results: The particle size was (35.79 ± 1.23) nm with polydispersity index (PDI) of 0.12 ± 0.03 when the optimized micelles ratio was at 3:7 of VE-TPGS and SHS15, which increased the solubility of Cur to 2.03 mg/mL in water. The entrapment efficiency and drug loading were 90.03% and 9.34%, respectively. The in vitro release profile showed a sustained release property compared with that of Cur. In addition, the relative bioavailability of micelles (AUC0~∞) compared with that of Cur (AUC0~∞) was 303.5% (P < 0.01). Conclusion: The Cur-micelles combined use of VE-TPGS and SHS15 shows great potential clinical application.
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@#The aim of this research were to prepare CI-921 mixed micelles(CI-Micelles), to establish a method for determining the entrapment efficiency of CI-Micelles, to optimize the formulation and to evaluate their in vitro properties. CI-Micelles were prepared by film dispersion. Dialysis and fitting were used to calculate true entrapment efficiency(EE)and drug loading(DL)of CI-Micelles. The influences of polymer concentration, polymer radio and hydrating media on the entrapment efficiency, drug loading and particle-size were investigated. The stability at 4 °C in 6 days was evaluated. The optimal formulation of CI-921-Micelles consisting of polymer concentration of 72 mg/mL, a mass radio of Pluronic F127/Solutol HS15 at mass ratio of 1 ∶2 and 5% glucose solution as hydrating medium, showed a EE of more than 90%, and mean particle-size of 17-25 nm and PDI< 0. 210. There were no significant changes to CI-Micelles in EE and particle-size after treatment at 4 °C for 6 days. The applied method of dialysis and fitting could be used to determine EE for micelles loaded with weakly basic drug which was difficult to meet sink conditions. Adjustment of the mass radio of Pluronic F127 to Solutol HS15 had resulted in uniform particle size distribution, high entrapment efficiency and drug loading capacity and better stability of CI-Micelles.
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OBJECTIVE: To prepare luteolin-loaded Solutol hsl5/Poloxamerl88 mixed micelles, evaluate their pharmaceutical property and study their anti-tumor activity. METHODS: The luteolin-loaded mixed micelles were prepared by thin-film hydration method. The particle size was measured by laser granulometry, and the morphology was observed under transmission electron microscope (TEM). The in vitro release behavior was determined by the dialysis method. Cell toxicity and uptake assays were employed to evaluate the anti-tumor activity. The targeting effect was studied by fluorescence labeling. RESULTS: The prepared luteolin-loaded mixed micelles showed spherical and regular shape with an average particle size of 66.43 nm and its entrapment efficiency was more than 80%. The 12 h-accumulated release ratio in vitro was up to 97.42%. The cytotoxicity of luteolin-loaded mixed micelles on human lung adenocarcinoma cell line A549 was significantly stronger than that of free luteolin and the uptake rate was improved. After injecting DiR-loaded mixed micelles into nude mouse, the drug begun to accumulate in tumors after 2 h and reached the highest concentration at 6 h which was significantly higher than that in other tissues. There remained strong drug distribution in the tumors after 12 h. CONCLUSION: The Solutol hs15/Poloxamer188 mixed micelles have small particle size and high entrapment efficiency and can enhance cell toxicity and uptake with certain passive targeting effect. It is a promising delivery system for anti-tumor drug.