Solid lipid nanoparticles (SLN) as potential carrier for human use: Interaction with human granulocytes

A solid lipid nanoparticle (SLN) formulation for intravenous injection was developed as drug carrier for potential human use. The lipid matrix was composed of glycerolbehenate (compritol), the dispersions stabilized by poloxamer 188 - a surfactant accepted for intravenous administration. The in vitro uptake of SLN by human granulocytes was determined by chemiluminescence (CL), cytotoxicity was assessed by viability measurements using the dimethylthiazolyl-diphenylytetrazolium (MTT) test. Adsorption layers of poloxamer on colloidal carriers reduce their phagocytic uptake in vitro and in vivo leading to prolonged circulation times in the blood, The SLN had a distinctly lower phagocytic uptake than poloxamer surface-modified polystyrene model carriers possessing prolonged circulation times in vivo. The cytotoxicity of the glyceride SLN was approximate to 10-fold below the one of polylactide/glycolide nanoparticles, The SLN might therefore be i.v. carriers with potentially prolonged circulation time and high toxicological acceptance. (C) 1997 Elsevier Science Ireland Ltd.