An Accessible and Scalable Pipette-Driven Microfluidic Platform for Lipid Nanoparticle Formulation

Takeda, Y. S.; Wang, F.; Gu, X.; Forster, J.; Hou, H.; Hemmati, P.; Partopour, B.; Maugeri, L.; Kim, Y.; Apel, S.; Norton, R.; Finelli, J.; Molaei, P.; Shafiee, S.; Li, S.; Lin, J.; Chiang, C.-w.; Mayo, M.; Ayehunie, S.; Akbari, S.; Mao, H.-Q.; Wang, T.-H.; Dehghani, M.

doi:10.64898/2026.11.06.757988

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bioRxiv · 10.64898/2026.11.06.757988

An Accessible and Scalable Pipette-Driven Microfluidic Platform for Lipid Nanoparticle Formulation

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Abstract

Advances in lipid nanoparticle (LNP) technology have increased the need for accessible and scalable methods that accelerate low-volume formulation screening. Here, we describe a disposable microfluidic mixer actuated by a positive-displacement pipette equipped with dual-chamber pipette tip, providing volumetric control at a fixed flow rate ratio without external microfluidic pumps. Computational fluid dynamics analysis predicted shorter micromixing times in the high-shear spiral channel than in the low-shear design. Across three benchmark lipid formulations, the high-shear mixer reproducibly generated smaller LNPs with higher mRNA encapsulation efficiency than the low-shear mixer or manual pipetting. Orthogonal characterization further revealed higher particle concentrations, structural features consistent with compact particles, more uniform mRNA loading, and a lower empty-particle fraction. LNPs prepared using the selected high-shear mixer mediated functional mRNA delivery in 2D cell cultures, a 3D human liver tissue model, and mice. Integration with a liquid-handling robot enabled automated screening of formulation parameters. Dimensionless mixing-time analysis guided enlargement of the mixer geometry for a separate production system, which produced 75 mL preparations at 150 mL/min with particle size and mRNA encapsulation efficiency comparable to those obtained with the small-scale mixer. This platform provides an accessible, automation-compatible approach to LNP formulation screening and a route to larger-scale production.

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Takeda, Y. S., Wang, F., Gu, X., Forster, J., Hou, H., Hemmati, P., Partopour, B., Maugeri, L., Kim, Y., Apel, S., Norton, R., Finelli, J., Molaei, P., Shafiee, S., Li, S., Lin, J., Chiang, C.-w., Mayo, M., Ayehunie, S., Akbari, S., Mao, H.-Q., Wang, T.-H., Dehghani, M.. 2026-11-09. An Accessible and Scalable Pipette-Driven Microfluidic Platform for Lipid Nanoparticle Formulation. https://doi.org/10.64898/2026.11.06.757988

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