Cost-Effective and Reproducible Preparation of mRNA-Loaded Lipid Nanoparticles Using a Conventional Laboratory-Scale Microfluidic Assembly System.

This protocol describes a standardized and economically accessible method for synthesizing mRNA-encapsulated lipid nanoparticles using routine laboratory equipment, including precision syringe pumps, Y-shaped glass microfluidic chips, and silicone tubing. Designed to address the cost and accessibility limitations of commercial microfluidic platforms, the system achieves performance metrics comparable to high-end devices while reducing equipment costs by 90%. By systematically optimizing hydrodynamic parameters (total flow rate: 12 mL/min; lipid-to-aqueous phase ratio: 3:1), the protocol enables consistent production of lipid nanoparticles with key quality attributes: high mRNA encapsulation efficiency (≥ 80%), narrow particle size distribution (100-120 nm, polydispersity index ≤ 0.2), and excellent storage performance (≥ 7 days at 4 °C). Key features • A low-cost mRNA@LNPs synthesis method is developed using common lab equipment, cutting costs by 90% while matching commercial systems' performance. • The LNP synthesis platform allows researchers to flexibly adjust hydrodynamic parameters to screen various lipid formulations.