Toward drug delivery into the brain: synthesis, characterization, and preliminary in vitro assessment of alkylglyceryl-functionalized chitosan nanoparticles.

A series of O-substituted alkylglyceryl chitosans with systematically varied degrees of grafting was prepared through synthetic steps that involved the protection of amino moieties via phthaloylation and employed for the formulation of aqueous nanoparticulate systems that may be capable of delivering drugs to the brain. Dynamic light scattering studies have shown that nanoparticles with physiologically relevant aqueous stabilities may be prepared following the partial quaternization of these alkylglyceryl-modified chitosans. Preliminary in vitro tests using a mouse-brain endothelial cell model have indicated the efficient cellular uptake of these nanoparticles and identified butylglyceryl chitosan and butylglyceryl N,N,N-trimethyl chitosan as promising materials for the formulation of colloidal systems that could act as drug carriers into the brain.