Life SciencesScience Insider
Have seen crime investigators in movies find bloods stain with chemical spray?
Vidunenahawula Website (National Institute of Fundamental Studies)
In movies you may have seen crime investigators spraying a chemical and when the room is darkened they find a blue glow in the places where blood is found. Have you ever thought how this process happens? The chemical that is sprayed is a mixture of hydrogen peroxide mixed with a chemical named luminol. The reaction between these two chemicals produce light but it doesn’t glow well without a help from a catalyst. The iron in the blood is one of the catalysts that intensify the glow. So the crime investigators would darken the room and spray the chemical. They would find where a blue glow appears and finds out whether it is blood. Even the blood is washed out it would still reveal by a blue glow.
