Ayehunie, S. | bioRxiv Science

bioRxiv2026

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

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.

bioengineering↗

bioRxiv2021

Multidose evaluation of 6,710 drug repurposing library identifies potent SARS-CoV-2 infection inhibitors In Vitro and In Vivo.

Identification of host factors contributing to replication of viruses and resulting disease progression remains a promising approach for development of new therapeutics. Here, we evaluated 6710 clinical and preclinical compounds targeting 2183 host proteins by immunocytofluorescence-based screening to identify SARS-CoV-2 infection inhibitors. Computationally integrating relationships between small molecule structure, dose-response antiviral activity, host target and cell interactome networking produced cellular networks important for infection. This analysis revealed 389 small molecules, >12 scaffold classes and 813 host targets with micromolar to low nanomolar activities. From these classes, representatives were extensively evaluated for mechanism of action in stable and primary human cell models, and additionally against Beta and Delta SARS-CoV-2 variants and MERS-CoV. One promising candidate, obatoclax, significantly reduced SARS-CoV-2 viral lung load in mice. Ultimately, this work establishes a rigorous approach for future pharmacological and computational identification of novel host factor dependencies and treatments for viral diseases.

microbiology↗