Advanced microfluidic techniques for the preparation of solid lipid nanoparticles: Innovations and biomedical applications

Solid lipid nanoparticles (SLNs) represent a promising category of nanocarriers used in medicine and cosmetics, offering enhanced drug protection, controlled release, and targeted delivery for both hydrophilic and lipophilic compounds. Conventional preparation methods, such as high-pressure homogenization and solvent emulsification-evaporation, face several challenges, including increased polydispersity, scaling limitations, and the presence of hazardous residual solvents. Microfluidic technology has emerged as a novel approach for preparing SLNs, addressing issues such as variable particle sizes and residual solvents by facilitating enhanced control over particle dimensions, morphology, and encapsulation efficiency. Microfluidics enables rapid and uniform mixing through micro-scale fluid dynamics, resulting in the production of homogeneous nanoparticles with adjustable characteristics. The review examines key parameters in microfluidic SLN preparation and categorizes various microfluidic chip designs and mixing techniques in detail, illustrating their unique advantages in controlling nanoparticle properties. Furthermore, this article provides a comprehensive overview of microfluidic SLN preparation, emphasizing its advantages over conventional methods, and explores the transformative potential of SLNs for advancing drug delivery systems, cosmetic formulations, and diagnostics. The integration of artificial intelligence (AI) and machine learning to optimize synthesis conditions and enhance reproducibility and scalability for industrial translation are also discussed.