Fig. 1From: Zebrafish: A Promising Real-Time Model System for Nanotechnology-Mediated Neurospecific Drug DeliveryCharacteristics of neurospecific drugs. The BBB is typically made up of the tight junctions in the endothelial cells surrounded by the astrocytes, pericytes and neurons. Neurospecific molecules should possess specific characteristics to be able to cross the blood–brain barrier (BBB). Preferred characteristics are: very small size with a diameter of less than 100 nm, low molecular weight preferably less than 400 Da, should be positively charged, spherical in shape and lipid solubilityBack to article page