O/W纳米乳液是由分散在连续水性介质中并通过表面活性剂分子稳定的油滴构成的各向同性胶体体系。纳米乳液在更广泛的技术领域拥有应用,更重要的是在制药行业。创新的基于纳米乳液的药物递送系统已被建议作为一种强大的替代策略,通过有用的封装手段,保护,并递送水溶性差的生物活性成分。因此,需要产生具有小且一致的液滴的乳液。各种研究表明,超声空化是制备药物级纳米乳液的一种可行且节能的方法。该方法在具有较低的奥斯特瓦尔德熟化率的稳定性方面提供了更显著的改进。同时,微结构反应器,例如,微通道,作为一种创新技术,它进一步实现了加速反应的组合方法,分析,和测量。最近取得的突破是通过微结构反应器控制产生精细和单分散的多重乳液。微通道的小内部尺寸显示特性,例如短扩散路径和高比界面面积,这增加了质量和传热速率。因此,超声空化与微观结构(微通道)的结合提供了产生较小的单分散纳米乳液体系的过程强化。这项研究是至关重要的,因为它将有助于不断创建新的基于纳米乳液的药物递送系统。在此之后,在O/W纳米乳液的生成中进行了微通道的制作及其与超声结合的设置,以及优化,以分析不同的操作参数对平均液滴直径和分散的纳米乳液产生的影响,除了监测纳米乳液的稳定性。还进行了扫描透射电子显微镜(STEM)图像用于液滴尺寸测量。总之,这项研究的结果令人鼓舞,这需要进行进一步的研究,以更好地理解耦合微通道与超声波生产药物级纳米乳液。
O/W nanoemulsions are isotropic colloidal systems constituted of oil droplets dispersed in continuous aqueous media and stabilised by surfactant molecules. Nanoemulsions hold applications in more widespread technological domains, more crucially in the pharmaceutical industry. Innovative nanoemulsion-based drug delivery system has been suggested as a powerful alternative strategy through the useful means of encapsulating, protecting, and delivering the poorly water-soluble bioactive components. Consequently, there is a need to generate an emulsion with small and consistent droplets. Diverse studies acknowledged that ultrasonic cavitation is a feasible and energy-efficient method in making pharmaceutical-grade nanoemulsions. This method offers more notable improvements in terms of stability with a lower Ostwald ripening rate. Meanwhile, a microstructured
reactor, for instance, microchannel, has further been realised as an innovative technology that facilitates combinatorial approaches with the acceleration of reaction, analysis, and measurement. The recent breakthrough that has been achieved is the controlled generation of fine and monodispersed multiple emulsions through microstructured reactors. The small inner dimensions of microchannel display properties such as short diffusion paths and high specific interfacial areas, which increase the mass and heat transfer rates. Hence, the combination of ultrasonic cavitation with microstructures (microchannel) provides process intensification of creating a smaller monodispersed nanoemulsion system. This investigation is vital as it will then facilitate the creation of new nanoemulsion based drug delivery system continuously. Following this, the fabrication of microchannel and setup of its combination with ultrasound was conducted in the generation of O/W nanoemulsion, as well as optimisation to analyse the effect of varied operating parameters on the mean droplet diameter and dispersity of the nanoemulsion generated, besides monitoring the stability of the nanoemulsion. Scanning transmission electron microscopy (STEM) images were also carried out for the droplet size measurements. In short, the outcomes of this study are encouraging, which necessitates further investigations to be carried out to advance a better understanding of coupling microchannel with ultrasound to produce pharmaceutical-grade nanoemulsions.