Luminol in Forensics

Luminol has played a hero's role in forensic science in recent years.

Luminol reacts with haemoglobin in blood stains which have been washed away (it is sensitive to 1ppm - one part per million!)

Forensic teams use a supplied mixture (above) and spray it all over a crime scene to detect suspected blood traces in a darkened room.

Flash techniques are available that pick up the reaction but leave the area around it visible in the picture.

In recent years this tool has become famous and has even graced the internet-based "stick figure" animation collections. Those not of a conservative temprament should have a look here.