What is luminol used for in forensic investigations?

Luminol is highly valued in forensic investigations for its ability to detect blood, even when it has been cleaned or diluted. When luminol is sprayed onto a surface, it reacts with hemoglobin, the oxygen-carrying protein in red blood cells, producing a bluish glow in the dark. This chemiluminescent reaction allows investigators to identify areas where blood is present, even if it has been washed away or obscured.

The effectiveness of luminol lies in its sensitivity and the ability to highlight potential crime scenes, making it an essential tool in the investigation of violent crimes or any situation where blood evidence may be crucial. This capability is particularly important as it provides forensic experts a way to discover and document potential evidence that would otherwise be overlooked.

The other options do not accurately reflect luminol's specific forensic application. For visualizing tire tracks, specific casting techniques and other materials are used. Detecting explosives typically involves different chemical assays designed for that purpose. Analyzing fingerprints requires methods such as powders or chemical fuming rather than luminol, which is not effective for this purpose.