Polymeric nanoparticles for the drug delivery to the central nervous system

Background: Nanoparticulate polymeric systems (nanoparticles, Np) have been widely studied for the delivery of drugs to a specific target site. This approach has been recently considered for the therapy of brain diseases. The major problem in accessing the central nervous system (CNS) is linked to the presence of the Blood-Brain Barrier (BBB). Objective: The present review deals with the different strategies that have been developed in order to allow the Np drug carriers to entry into the CNS parenchyma. Among these, the use of magnetic Np, Np conjugation with ligands for BBB receptors, with antibodies, and the use of surfactants have been considered.Methods: All the literature available is reviewed in order to highlight the potentiality of this drug delivery system to be used as drug carrier for the treatment of CNS pathologies.Conclusions: Polymeric Np showed to be promising carriers for the CNS drug delivery, due to their potential both in encapsulating drugs, hence protecting them from the body excretion and metabolism, and in delivering active agents across the BBB without inflicting any damage to the BBB. Different polymers have been used and different strategies have been applied; among these, the use of specific ligands, in order to render the delivery of drugs to CNS more specific, has been recently considered. At present, some clinical trials appeared for the use of these drug carriers, but none is related to the treatment of CNS diseases.