Solid lipid nanoparticles as vehicles of drugs to the brain: Current state of the art

[Display omitted] •BBB acts as a physical barrier restricting the drug types that can reach the brain.•Various methods can assess whether a formulation is suitable for brain delivery.•Crossing the BBB may be achieved by using NPs.•SLN are frequently proposed as drug delivery systems to the CNS.•Targeted SLN can improve the interaction between NPs and BBB endothelial cells. Central nervous system disorders are already prevalent and steadily increasing among populations worldwide. However, most of the pharmaceuticals present on world markets are ineffective in treating cerebral diseases, because they cannot effectively cross the blood brain barrier (BBB). Solid lipid nanoparticles (SLN) are nanospheres made from biocompatible solid lipids, with unique advantages among drug carriers: they can be used as vehicles to cross the BBB. This review examines the main aspects surrounding brain delivery with SLN, and illustrates the principal mechanisms used to enhance brain uptake of the delivered drug.