Science Buddies: "Ask an Expert"

Hello!
For my project I am testing how black light reveals different types of animal blood. I was wondering if you could answer a few questions that I have about luminol and blacklights.
--Why does luminol react with blacklight?
--Does luminol damage the DNA structure of the blood being sprayed with the chemical?
--What is luminol made of?
Any information that you have will be very helpful!
Thanks!
Chrissy Swartz

Interesting question, Chrissy.

One reference I found said that Luminol is mixed with Hydrogen Peroxide and reacts with the hemoglobin in blood. When the luminol and hydrogen peroxide come in contact with hemoglobin it causes an oxidation reaction. The oxidation is accelerated by a catalyst. The catalyst is the iron in the hemoglobin and it causes chemiluminescence. This "glow" is visible in a darkened environment. There is no UV lamp or any other kind of illumination needed to see this reaction. There is another substance with the trade name of Hemaglow that has isopropyl alcohol in it, which would also lyse the red blood cells. But the company states that DNA testing would be possible using it.

If hydrogen peroxide is used, then the red cell walls would be lysed, and I would have thought that the DNA would likely be destroyed. Evidently, that is not true:

http://www.redwop.com/technotes.asp?ID=118

Do a wikipedia search on "Luminol": It explains the chemical reactions and the content of the substance.

http://en.wikipedia.org/wiki/Luminol#_note-3

There is also a "How stuff works" article on how luminol works:
http://people.howstuffworks.com/luminol.htm

One of my favorite sites for finding out more about things is called http://www.howstuffworks.com

Check out this link to find out more about Luminol:
http://science.howstuffworks.com/luminol.htm

I found this site by doing a Google search "luminol"

If you read the article at the link above you will get your questions answered.

Enjoy!

Thank you so much for getting back to me so quickly! This information will be very helpful to me for my research.
Chrissy Swartz