What is a primary advantage of using Ninhydrin on porous surfaces?

The primary advantage of using Ninhydrin on porous surfaces is its high sensitivity. Ninhydrin is particularly effective for developing latent fingerprints on porous materials such as paper, cardboard, and untreated wood. This is due to its ability to react with amino acids present in the sweat and other residues left by the fingers. When Ninhydrin interacts with these amino acids, it forms a colored compound, which makes the fingerprints visible.

The high sensitivity of Ninhydrin allows for the detection of even very faint impressions that may not be visible through other methods. This is crucial in forensic investigations, where finding every possible piece of evidence can be key to solving a case. Detecting latent prints that other methods might miss can significantly enhance the chances of identification and can lead to breakthroughs in investigations.

In contrast, while speed, color change, and cost-effectiveness are important factors in forensic techniques, they do not capture the primary advantage of Ninhydrin when applied on porous surfaces, which is significantly tied to its sensitivity and ability to visualize prints effectively.