Microfluidic Approaches for Gene Delivery and Therapy

Gene editing techniques such as Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR/Cas9) have been developed to target a gene into cells, which greatly expands their application for various immunotherapies and genetic disorders. Intracellular delivery is critical in the development of new therapies and is the process of introducing external cargos such as DNAs, RNAs, plasmid DNAs, proteins, or nanomaterials into the cytosol or nucleus of living cells to genetically alter and reprogram innate cell function. Traditional methods such as bulk electroporation or viral vectors face a few drawbacks, including low cell viability, cytotoxicity, and uneven material delivery, which has sparked interest in the creation of more effective intracellular delivery systems. Microfluidic devices offer a promising solution for intracellular delivery of genetic materials because of their low usage of materials, high throughput, high customizability, and flexibility. Microfluidic devices have been developed to deliver a wide range of different payloads into different cell types with the highest level of precision and efficiency. In this chapter, we review recent advances in microfluidic approaches for delivery and discuss new opportunities as well as challenges for clinical applications. We highlight carrier-mediated and membrane disruption-based methods, including electro transfection, sonoporation and mechanoporation (microinjections, nanoneedle arrays, cell-squeezing, and hydroporation). We give the limitations, applications, and analysis, as well as considering the development of next-generation intracellular delivery platforms enabled by micro/nanoengineered technology.