Which chemical test is known for producing a chemiluminescence lasting over 15 minutes to detect blood?

Luminol is well-known for its ability to detect blood through a process of chemiluminescence, which makes it particularly useful in forensic science. When Luminol comes into contact with hemoglobin, it reacts to produce a blue glow that can last for over 15 minutes, allowing investigators ample time to observe and photograph the evidence. This property of sustained luminescence is especially valuable in crime scene investigations, where conditions may not always be optimal for immediate assessment.

In contrast, other tests such as Phenolphthalein, Benzidine, and Leucomalachite green do not exhibit the same long-lasting luminescent properties. Phenolphthalein and Benzidine primarily produce color changes rather than light emissions, and Leucomalachite green, while effective in detecting blood, does not have the luminescence attribute that Luminol is known for. Therefore, the distinctive chemiluminescent reaction of Luminol makes it the most suitable choice for this particular application in forensic investigations.