In the spotlight of successful breakthrough of the COVID-19 mRNA vaccines, lipid nanoparticles are becoming an important vehicle to deliver a variety of therapeutics. The encapsulation of mRNA using lipids is a self-organizing process that necessitates fast mixing to achieve uniform supersaturation. This is achieved in a confined impinging jet reactor (CIJR) where two input jets collide and fast mix in the mixing chamber. While CIJR is not a new mixing technology, it stands out for its capability to achieve mixing times below a millisecond. This study presents a critical review of major studies concerning CIJRs, starting with the CIJRs’ structures and flow characterization, through experimental and numerical studies, and closing with successful applications in a wide range of chemical/pharmaceutical processes. The detailed mixing principles, scaling-up, and mechanisms of making nanoparticles are discussed focusing mainly on the hydrodynamic aspect. The objective of the review is to supply essential information for the optimized design and operation of CIJRs, catering to both industry and academia.

中文翻译：

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从 mRNA-LNP 疫苗生产的角度回顾有限冲击射流反应器 (CIJR)


在 COVID-19 mRNA 疫苗取得成功突破的聚光灯下，脂质纳米颗粒正在成为提供各种治疗药物的重要载体。使用脂质封装 mRNA 是一个自组织过程，需要快速混合以实现均匀的过饱和。这是在受限冲击射流反应器 (CIJR) 中实现的，其中两个输入射流在混合室中碰撞并快速混合。虽然 CIJR 不是一项新的混合技​​术，但它因其能够实现低于毫秒的混合时间而脱颖而出。本研究对有关 CIJR 的主要研究进行了批判性回顾，从 CIJR 的结构和流动表征开始，通过实验和数值研究，最后以在广泛的化学/制药过程中的成功应用为结束。讨论了详细的混合原理、放大和纳米颗粒的制备机制，主要集中在流体动力学方面。审查的目的是为 CIJR 的优化设计和运行提供必要的信息，以满足工业界和学术界的需求。