Abstract:
Solid lipid nanoparticles (SLNs) have attracted intense interest as carriers capable of enhancing the solubility, stability, and bioavailability of a broad spectrum of bioactive. Production techniques fall into three broad families-physical, chemical, and biological (“green”)-each with distinct advantages, limitations, and scale up considerations. Physical methods use mechanical forces such as high-pressure homogenization, ultrasonication, and membrane contractors to reduce particle size and create stable dispersions. Chemical methods rely on solvent-based processes like solvent emulsification–evaporation, solvent diffusion, microemulsion formation, and solvent injection. Biological methods employ natural materials or bio-inspired processes, including enzyme-mediated lipid modification, biosurfactant-assisted formation, and fermentation-derived lipids. This chapter provides a systematic overview of the major methodologies, clarifies common sources of confusion, and highlights key process parameters that govern particle size, polydispersity, and long term stability.
Keywords:
Solid lipid nanoparticles, High‑Pressure Homogenisation, Ultrasonication, Solvent Emulsification–Evaporation, Solvent Diffusion (Emulsification–Diffusion), Solvent Injection (Nanoprecipitation).
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