Influence of sonication and in vitro evaluation of nifedipine self-nanoemulsifying drug delivery system

In order to develop a self-nanoemulsifying system, three components, olive oil, Tween 80, and Capmul, were used to construct a ternary phase diagram that helped to find the optimum formulation, which was loaded with nifedipine. The effect of sonication on drug loading was also evaluated. After that, measurement of the droplet size, size distribution, zeta potential, and scanning electron microscopy were conducted for evaluation and characterisation of the formulations. The phase diagram of four formulations showed nanosizes below 200 nm; however, only one was selected to be loaded with nifedipine. The selected formulation had the lowest droplet size of 98 nm and size distribution 0.192, and was composed of 48% Tween 80, 32% Capmul, and 20% olive oil. The nifedipine self-nanoemulsifying drug delivery system (SNEDDS) showed a significant change in the particle size (97 nm) and size distribution (0.257) after sonication. Its zeta potential was -32.3 mV indicating good stability. The SEM photographs of nifedipine showed particles with spherical shape and smooth surface. Finally, a self-nanoemulsifying formulation containing nifedipine, loaded in olive oil, was successfully prepared by mixing the oil with various types of surfactants and co-surfactants. A significant nifedipine self-nanoemulsifying system was developed and significantly improved accordingly.

为开发自纳米乳化系统（self-nanoemulsifying system），本研究选用橄榄油、吐温80（Tween 80）与Capmul三种组分构建三元相图，以筛选最优处方并用于负载硝苯地平（nifedipine），同时评估了超声处理对载药量的影响。随后，通过测定液滴粒径、粒径分布、ζ电位（zeta potential）并结合扫描电子显微镜（scanning electron microscopy, SEM）表征，对处方进行质量评价与特性分析。四种处方的相图结果显示其纳米粒径均低于200 nm，但仅筛选出一处方用于负载硝苯地平。该优选处方的初始液滴粒径为98 nm，粒径分布为0.192，处方组成为48%吐温80、32% Capmul与20%橄榄油。经超声处理后，所制硝苯地平自纳米乳化给药系统（self-nanoemulsifying drug delivery system, SNEDDS）的粒径变为97 nm，粒径分布为0.257，其ζ电位为-32.3 mV，表明体系具备良好的稳定性。硝苯地平样品的SEM照片显示，所得颗粒呈球形且表面光滑。本研究最终通过将橄榄油与多种表面活性剂及助表面活性剂混合，成功制备了负载硝苯地平的自纳米乳化处方，开发出性能优异的硝苯地平自纳米乳化系统并实现了性能的显著优化提升。