Evans blue dye solution was used to observe the effect of a viral protein on two pre-defined barriers of the body i.e. the blood brain barrier (BBB) and the placental barrier (PB). This dye has strong affinity for serum albumin and does not cross these barriers under natural conditions. As all the dye gets bound to albumin, all the neural tissues and embryonic tissues remain unstained. When the BBB and PB are compromised due to the breach of these barriers, albumin-bound Evans blue enters the CNS and the placenta.