title: Preparation and in vivo toxicity study of solid lipid microparticles as carrier for pulmonary administration.
abstract: The purpose of this research was to investigate the effects of processing conditions on the characteristics of solid lipid microparticles (SLM) with a potential application as carriers for pulmonary administration. Compritol (5.0% wt/wt) SLM dispersions were prepared by rotor-stator homogenization, at different surfactant concentrations and emulsification times. The SLM were characterized, in terms of morphology and size, after lyophilization and sterilization by autoclaving process. In vivo assessment was carried out in rats by intratracheal instillation of either placebo or SLM dispersion, and by bronchoalveolar lavage for cytological analysis. Mean particle size of 4 to 5 microm was achieved using 0.3% and 0.4% (wt/wt) of emulsifier (Poloxamer 188) and emulsification times of 2 and 5 minutes. The particles showed spherical shape and smooth surface. The morphology of microparticles, the size, and the size distribution were not substantially modified after lyophilization and sterilization. Total cell counts showed no significant differences between placebo and SLM 0.5% or 2.5% groups. Regarding cytology, percentage of polymorphonuclear neutrophils and macrophages did not significantly differ between groups. These results suggest that a single intratracheal administration of the SLMs does not induce a significant inflammatory airway response in rats and that the SLMs might be a potential carrier for encapsulated drug via the pulmonary route.
authors.affiliation: Dipartimento di Scienze del Farmaco, University of Sassari, via Muroni 23/a, 07100 Sassari, Italy.
authors.forename: Vanna
authors.initials: V
authors.lastname: Sanna
authors.forename: Nathalie
authors.initials: N
authors.lastname: Kirschvink
authors.forename: Pascal
authors.initials: P
authors.lastname: Gustin
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Gavini
authors.forename: Isabelle
authors.initials: I
authors.lastname: Roland
authors.forename: Luc
authors.initials: L
authors.lastname: Delattre
authors.forename: Brigitte
authors.initials: B
authors.lastname: Evrard
mesh_terms: D000818:Animals; D002626:Chemistry, Pharmaceutical; D004337:Drug Carriers; D008055:Lipids; D008168:Lung; D008297:Male; D008863:Microspheres; D010316:Particle Size; D051381:Rats; D017207:Rats, Sprague-Dawley; D013678:Technology, Pharmaceutical; D014116:Toxicology
chemical_list: D004337:Drug Carriers; D008055:Lipids