Preparation and characterization of dexamethasone lipid nanoparticles by membrane emulsification technique, use of self-emulsifying lipids as a carrier and stabilizer

Self-emulsifying lipids (SEL) were used as a stabilizer for the preparation of dexamethasone lipid nanoparticles by membrane emulsification employing Shirasu porous glass. The effect of process and formulation parameters on the size and polydispersity and dexamethasone solubility in lipids and its release from lipid nanoparticles were investigated. Lipid phase pressure (40-80 kPa), membrane pore-size (0.1 - 0.4 mu m) and agitation speed (300 - 900 rpm) did not affect the size and polydispersity of SEL. However, the size was increased with increasing lipid content and fatty acid chain of the lipid. Sizes of < 250 nm were achieved from TEGO(R) care:Gelucire(R) blend and it increased to 487 nm by adding 20% w/w of hard fat. The highest solubility of dexamethasone was found in TEGO(R) care 450 (29 mg/g). Release from the lipid nano-dispersions was extended with no burst effect and the absolute release was increased with increasing lipid content.