Making Animal Skin Transparent

We have several ways to look inside the human body. The CT scan is computerized tomography which uses X-rays and computers to create highly detailed images of our bones and tissues. MRI or magnetic resonance imaging uses magnetic fields and radio waves to create high-def images of tissues and organs. Both are non-invasive and help doctors diagnose.  

But there may be a new way to look inside the body. Rubbing FDA-approved food dyes on the skin of a living animal can render it almost transparent! The idea isn’t new. Scientists have been doing this for years using harsh chemicals which are fine with dead animals but toxic to live ones.   

This new study found that rubbing a common food dye – tartrazine – on the shaved skin of a mouse made its skin transparent and gave it an orange hue. The more dye they applied; the more transparent the mouse’s skin became. The researchers could see with the naked eye, the animal’s heart beating, food passing through its intestine, and detailed muscle action.  

A red dye allowed them to see through the animal’s skull into the brain to observe neuronal brain activity. When they injected dye under the skin, they saw deeper into the tissues. This means scientists may get to study animals without sedating or dissecting them.  

However not all tissues can be made transparent, and the effect is temporary. Maybe this is a step closer to “Star Trek” medicine where a future “Bones” can diagnose patients with a wave of his tricorder!