Which development method is commonly used for latent fingerprints on nonporous surfaces?

Which development method is commonly used for latent fingerprints on nonporous surfaces?

• A. Cyanoacrylate fuming
• B. Ninhydrin
• C. Physical Developer
• D. Iodine fuming

Answer: (A)

Cyanoacrylate fuming is the method most often used to develop latent fingerprints on nonporous surfaces. The fumes interact with the moisture and residue (such as amino acids) left by the fingerprint, initiating polymerization of the cyanoacrylate and forming a hard, white polymer that adheres to the ridge patterns. This creates a durable, visible image on materials like glass, plastic, and metal, which can be photographed or enhanced further. On porous surfaces, other methods are preferred because they react with components of the fingerprint (like amino acids or lipids) that are more accessible in the porous matrix. Iodine fuming is rapid but temporary and works best on porous items; prints developed this way fade or rearrange and aren’t ideal for long-term records. Ninhydrin targets amino acids and is similarly suited to porous materials rather than nonporous ones. Physical Developer is a sensitive chemical for porous substrates as well, relying on diffusion through the material, so it isn’t typically used for nonporous items.

Cyanoacrylate fuming is the method most often used to develop latent fingerprints on nonporous surfaces. The fumes interact with the moisture and residue (such as amino acids) left by the fingerprint, initiating polymerization of the cyanoacrylate and forming a hard, white polymer that adheres to the ridge patterns. This creates a durable, visible image on materials like glass, plastic, and metal, which can be photographed or enhanced further.

On porous surfaces, other methods are preferred because they react with components of the fingerprint (like amino acids or lipids) that are more accessible in the porous matrix. Iodine fuming is rapid but temporary and works best on porous items; prints developed this way fade or rearrange and aren’t ideal for long-term records. Ninhydrin targets amino acids and is similarly suited to porous materials rather than nonporous ones. Physical Developer is a sensitive chemical for porous substrates as well, relying on diffusion through the material, so it isn’t typically used for nonporous items.