The possibility of preparing solid lipid nanoparticles (SLN) by means of an alternative technique to the most diffused high pressure homogenization and dilution of micro-emulsion was tested. SLN formulations were therefore prepared by a solvent injection procedure (SI), by changing the lipid component (palmitic or stearic acid) and using the lipophilic antioxidant agent idebenone (IDE) as a model drug. SI-SLN showed a good compatibility with the encapsulated drug and interesting sizes (around 160–180 nm) and a negative surface charge (zeta potential around −30 mV) for systemic administration purposes. This method of preparation allowed to obtain smaller nanoparticles and higher drug encapsulation efficiency than a micro-emulsion procedure. SI-SLN were stable upon storage at room temperature for up to 6 months and can be also successfully freeze-dried. A slow and prolonged drug release was observed in vitro from these systems. A biological assay proved that the incorporation of IDE in the SLN matrix maintained or in some cases increased drug protecting activity against free radical-induced oxidative damage of astrocyte cell cultures.
Journal of Biomedical Nanotechnology (JBN) is a peer-reviewed multidisciplinary journal providing broad coverage in all research areas focused on the applications of nanotechnology in medicine, drug delivery systems, infectious disease, biomedical sciences, biotechnology, and all other related fields of life sciences.