Recent approaches to mRNA vaccine delivery by lipid-based vectors prepared by continuous-flow microfluidic devices

Advancements in nanotechnology have resulted in the introduction of several nonviral delivery vectors for the nontoxic, efficient delivery of encapsulated mRNA-based vaccines. Lipid- and polymer-based nanoparticles (NP) have proven to be the most potent delivery systems, providing increased delivery efficiency and protection of mRNA molecules from degradation. Here, the authors provide an overview of the recent studies carried out using lipid NPs and their functionalized forms, polymeric and lipid-polymer hybrid nanocarriers utilized mainly for the encapsulation of mRNAs for gene and immune therapeutic applications. A microfluidic system as a prevalent methodology for the preparation of NPs with continuous flow enables NP size tuning, rapid mixing and production reproducibility. Continuous-flow microfluidic devices for lipid and polymeric encapsulated RNA NP production are specifically reviewed.