Faculty of Engineering and the Environment, University of Southampton, Southampton, UK.
Nanotechnology. 2012 Sep 21;23(37):375602. doi: 10.1088/0957-4484/23/37/375602. Epub 2012 Aug 24.
Microreactors have been shown to be a powerful tool for the production of nanoparticles (NPs); however, there is still a lack of understanding of the role that the microfluidic environment plays in directing the nanoprecipitation process. Here we investigate the mechanism of nanoprecipitation of block copolymer stabilized organic NPs using a microfluidic-based reactor in combination with computational fluid dynamics (CFD) modelling of the microfluidic implementation. The latter also accounts for the complex interplay between molecular and hydrodynamic phenomena during the nanoprecipitation process, in order to understand the hydrodynamics and its influence on the NP formation process. It is demonstrated that the competitive reactions result in the formation of two types of NPs, i.e., either with or without loading organic actives. The obtained results are interpreted by taking into consideration a new parameter representing the mismatching between the aggregations of the polymers and actives, which plays a decisive role in determining the size and polydispersity of the prepared hybrid NPs. These results expand the current understanding of the co-nanoprecipitation mechanism of active and block copolymer stabilizer, and on the role exerted by the microfluidic environment, giving information that could be translated to the emerging fields of microfluidic formation of NPs and nanomedicine.
微反应器已被证明是生产纳米颗粒 (NPs) 的有力工具；然而，对于微流环境在指导纳米沉淀过程中所起的作用，我们仍然缺乏了解。在这里，我们使用基于微流的反应器结合计算流体动力学 (CFD) 对微流实施的建模来研究嵌段共聚物稳定的有机 NPs 的纳米沉淀机制。后者还考虑了纳米沉淀过程中分子和流体力学现象之间的复杂相互作用，以了解流体动力学及其对 NP 形成过程的影响。结果表明，竞争反应导致形成两种类型的 NPs，即具有或不具有负载有机活性物质的 NPs。通过考虑一个代表聚合物和活性物质聚集不匹配的新参数来解释获得的结果，该参数在决定所制备的杂化 NPs 的尺寸和多分散性方面起着决定性的作用。这些结果扩展了对活性物质和嵌段共聚物稳定剂共纳米沉淀机制的现有理解，以及微流环境所发挥的作用，为新兴的 NPs 微流体制备和纳米医学领域提供了有价值的信息。
