This study focuses in particular on the evaluation of a delivery system for brain therapeutic targeting in Mucopolysaccharidosis type I (MPS I) and type II (MPS II).MPS I (Hurler/Scheie Syndrome, MIM #607014, #607015, #607016) is an autosomic recessive disorder due to the deficit of α-L-iduronidase (IDUA, EC 3.2.1.76) [4], while MPS II (Hunter Syndrome, MIM #309900) is an X-linked recessive disease caused by the deficit of iduronate 2-sulfatase (IDS, EC3.1.6.13) [5]. Here, IDS is linked to mucopolysaccharidosis type 2.