目的选用乳铁蛋白(TJf)为脑靶向配体,构建受体介导的脑靶向姜黄素纳米脂质载体(Lf-Cur—NLCs),对其理化性质及体内脑靶向效率进行评价。方法采用熔融一乳化法制备姜黄素纳米脂质载体(Cur—NLCs),通过静电作用在姜黄素纳米脂质载体表面吸附乳铁蛋白,得到不同乳铁蛋白含量修饰的Lf-Cur.NLCs。考察其形态、粒径、Zeta电位、血浆稳定性及在含1%聚山梨酯80的生理盐水中的释放行为;选取乳铁蛋白质量浓度分别为O.5、1.5、2.0mg·mL-1。时制备的载荧光显像剂NIRD.15的乳铁蛋白修饰纳米脂质载体(分别标记为Lf-NLC、E13-NLC和El-NLC)进行小鼠尾静脉注射,采用活体成像系统观察小鼠活体及离体器官中药物荧光强度,评价Lf-NLCs的脑靶向性。结果姜黄素纳米脂质载体和乳铁蛋白姜黄素纳米脂质载体体系均呈类球形。姜黄素纳米脂质载体平均粒径(187.5±4.7)nm,Zeta电位(-23.7±2.9)mV。乳铁蛋白姜黄素纳米脂质载体体系平均粒径范围167.8~299.9nm,Zeta电位的分布范围为-26.87~-13.03mV。乳铁蛋白与姜黄素纳米脂质载体的静电吸附作用存在一个吸附与解吸附的过程,当乳铁蛋白浓度为2.0mg·mL-1,温孵时间为6h时,乳铁蛋白在姜黄素纳米脂质载体表面的吸附趋于饱和。乳铁蛋白姜黄素纳米脂质载体在血浆中具有较好的稳定性,体外释放具有明显的缓释特征。与NLCs相比,尾静脉注射5min后,姜黄素纳米脂质栽体在脑内有较强的荧光,说明姜黄素纳米脂质载体能主动靶向脑组织,同时研究发现E13-NLC的脑靶向效果最好。结论本实验利用静电吸附作用成功构建了具有脑靶向功能的姜黄素纳米脂质栽体,避免了靶向载体设计中的化学合成过程,工艺简单,具有较好的发展前景,但载体脑靶向能力与乳铁蛋白的用量有关。
OBJECTIVE To construct receptor-mediated lactoferrin-modified curcumin-loaded nanostructured lipid carriers (Lf- Cur-NLCs) and investigate its in vitro physieochemical properties and in vivo brain targeting efficiency. METHODS Cur-NLCs were prepared by melt-emulsification method, and then lactoferrin(Lf) was adsorbed onto the surface of Cur-NLCs via electrostatic interaction to form Lf-Cur-NLCs. Lf-Cur-NLCs with different concentrations of Lf were characterized in terms of shape, diameter, Zeta potential, serum stability and in vitro release of Lf-Cur-NLCs in saline containing 1% Tween 80. Additionally, Lf-NLCs labeled with NIRD-15, a fluorescent imaging agent, were prepared with Lf at concentrations of 0. 5, 1.5 and 2. 0 mg ~ mL-I ( marked for Lf1 -NLC, Lf3-NLC, and Lf4-NLC, respectively). After iv injection in mice, living animal imaging system was used to observe the fluorescence intensity of NIRD-15 in the living animals and isolated organs to evaluate the brain targeting of Lf-NLCs. RESULTS Cur-NLCs were spherical with average particle size of( 187.5 + 4. 7 ) nm and Zeta potential of( - 23.7 + 2. 9 ) inV. The average diameter of Lf-Cur-NLCs with spherical shape was between 167.8 - 299. 9 nm. The Zeta potential was between - 26. 87 - - 13.03 mV. When the concentration of Lf was 2. 0 mg ~ mL- l and the incubated time was 6 h, the adsorption of Lf at the surface of the Cur-NLCs was saturated. Lf-Cur-NLCs were stable in serum, and the release of Cur from Lf-Cur-NLCs was slowed down. Compared with NLCs, there was a strong fluores- cence in the brain after iv injection of Lf-NLCs, indicating that ~-NLCs were more effective than NLCs in brain targeting, while Lf3- NLCs were the most effective one. CONCLUSION Lf-NLCs are constructed successfully for brain targeting via electrostatic adsorp-tion. The established process avoids chemical synthesis in the targeting drug delivery system design. However, the ability of brain tar- geting of the carriers is related with the amount of Lf.