Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, PR China.
Drug Dev Ind Pharm. 2010 May;36(5):508-17. doi: 10.3109/03639040903264397.
The aim of this study was to design bufadienolides-loaded nanostructured lipid carriers (BU-NLCs) to reduce the degradation of drugs in rat plasma.
BU-NLCs were prepared by a modified melt-emulsification ultrasonic technique and then characterized by particle size distribution, zeta potential, entrapment efficiency, differential scanning calorimetry, and X-ray diffraction.
The optimal formulation consisted of glyceryl monostearate 1.8%, medium-chain triglyceride 0.75%, oleic acid 0.45%, Lipoid E-80 1.5%, Pluronic F68 1.0%, and sodium deoxycholate 0.25%. The particle size distribution and the range of zeta potential of BU-NLCs were 104.1 +/- 51.2 nm and -15 to -20 mV, respectively. The entrapment efficiencies of the bufadienolides were all above 85%. In the enzymolysis study, the chemical stability of cinobufagin (C) in BU-NLCs was enhanced by being encapsulated in particles of NLC and adjusting the pH of the surrounding environment to 7.0. The half-life of C was 17-fold longer than that in bufadienolides solution. The in vitro release showed that the release from BU-NLCs was slower than from bufadienolides solution and followed the Weibull equation. Differential scanning calorimetry and X-ray diffraction showed that BU-NLC was in an amorphous state after lyophilization.
These results indicated that NLC could be developed as a carrier with improved drug plasma stability and offering controlled drug release.
本研究旨在设计布福苷元负载的纳米结构脂质载体（BU-NLCs）以减少药物在大鼠血浆中的降解。
采用改良的熔融乳化超声技术制备 BU-NLCs，并通过粒径分布、Zeta 电位、包封效率、差示扫描量热法和 X 射线衍射进行表征。
最佳配方由 1.8%甘油单硬脂酸酯、0.75%中链甘油三酯、0.45%油酸、1.5% Lipoid E-80、1.0% Pluronic F68 和 0.25%脱氧胆酸钠组成。BU-NLCs 的粒径分布和 Zeta 电位范围分别为 104.1±51.2nm 和-15 至-20mV。布福苷元的包封效率均在 85%以上。在酶解研究中，通过将蟾毒灵（C）包裹在 NLC 颗粒中并将周围环境的 pH 值调节至 7.0，可增强其在 BU-NLCs 中的化学稳定性。C 的半衰期比布福苷元溶液延长了 17 倍。体外释放结果表明，BU-NLCs 的释放速度比布福苷元溶液慢，且符合 Weibull 方程。差示扫描量热法和 X 射线衍射表明，冻干后 BU-NLC 呈无定形态。
这些结果表明，NLC 可作为一种载体，提高药物的血浆稳定性并提供控释效果。
