Lipid-based nanocarriers are promising tools to deliver APIs, including peptides, as their nanosize are in favour of transepithelial transport.
Solid Lipid Nanoparticles (SLN) are composed of lipids in solid state at room and body temperature, usually long chain triglycerides or partial glyceride, fatty acids, waxes, etc.
Precirol® ATO 5 is the preferred solid lipid carrier as it is digestible and exhibits a low melting point (around 50-55°C).
Nanostructured Lipid Carriers (NLC) contain both solid and liquid lipid at room and body temperature. The liquid lipids act as crystallization inhibitors of the solid lipid.
Capryol® 90 is the preferred liquid lipid excipient.
Many techniques are being described in the scientific literature to prepare SLN and NLC as reviewed by Dumont et al (2018) and schematized below.
A hot emulsion is pushed under high pressure through a few micrometer orifice engendering a high shear stress, which in turn disrupts the droplets down to the nanosize range. The nanoparticles are obtained upon cooling of the nanoemulsion.
The conditions of process to obtain reproducible nanoparticles have been described by Dumont et al (2019).