纳米白藜芦醇脂质体的物理化学稳定性研究

Study on Physicochemical Stability of Nano-Resveratrol Liposomes

纳米载药脂质体的物理化学稳定性是其实际应用中的关键问题。本文采用薄膜旋转蒸发法-超声法制备了白藜芦醇纳米脂质体(RES-Lip),通过透射电镜观察其微观形貌,并考察RES-Lip的物理化学稳定性。通过电导法测定了RES-Lip的相变温度(Tm)及其在凝聚过程的凝聚速率常数(Kco)和表观活化能(Eco);采用动态透析-紫外分光光度法研究了温度和pH对RES-Lip降解的影响。结果表明,RES-Lip为球形囊泡结构,粒径小于100nm, RES-Lip的相变温度为64℃,凝聚速率常数Kco随体系温度升高而升高,表观活化能Eco为86.056kJ/mol, RES-Lip的降解符合一级动力学模型,降解的表观活化能Ea为59.3157kJ/mol,降解过程是吸热、自发、熵增过程。本实验制备得到的RES-Lip在4℃、pH 7.40的条件下储存稳定性较好。

The physicochemical stability is an important problem of nano-drug-loading liposomes in practical application. In this paper, nano-resveratrol liposomes(RES-Lip) were prepared by film rotary evaporation and ultrasonic method, characterized by transmission electron microscope(TEM), and the physicochemical stability was investigated. The phase transition temperature(Tm), condensation rate constant(Kco) and apparent activation energy(Eco) in the condensation process of RES-LIP were measured by the conductivity method. The effects of temperature and pH on the degradation of RES-Lip were studied by dynamic dialysis-ultraviolet spectrophotometer. The results showed that RES-Lip were spherical vesicles with the particle sizes less than 100 nm. The phase transition temperature of RES-Lip was 64 ℃. The condensation rate constant Kcoof RES-Lip increased with the increase of temperature. The apparent activation energy Ecowas 86.056 kJ/mol. The degradation of RES-Lip belonged to the first-order kinetic model, the apparent activation energy of degradation(Ea) was 59.3157 kJ/mol, and the degradation process was endothermic, spontaneous and entropy-increased process. The RES-Lip obtained in this experiment could be stored at 4 ℃ and pH 7.40 in practical application.