[A study of developing fingermarks by nano-titanium dioxide shielding ultraviolet-ray]

Area of Science:

• Forensic Science
• Materials Science
• Nanotechnology

Context:

• Developing latent fingermarks on colored or fluorescent surfaces presents significant challenges for traditional forensic methods.
• Existing techniques often struggle with poor contrast and background interference on these difficult substrates.

Purpose:

• To introduce a novel fingermark development technique utilizing nano-titanium dioxide's ultraviolet (UV)-shielding properties.
• To evaluate the efficacy of rutile nano-titanium dioxide for developing fingermarks on challenging surfaces.

Summary:

• Rutile nano-titanium dioxide (TiO2) particles, approximately 30 nm in size, effectively shield UV light (<400 nm).
• These nanoparticles selectively adsorb onto fingermark ridges, creating visible marks with high contrast under 365 nm UV irradiation.
• The developed fingermarks exhibit smooth ridges and clear detail, outperforming traditional methods like cyanoacrylate fuming with dye staining.

Impact:

• This nano-TiO2 technique provides a superior, convenient, and economical solution for developing fingermarks on colored and fluorescent surfaces.
• The method demonstrates effectiveness on both fresh and old fingermarks on non-porous objects.
• It offers a promising advancement in forensic science with broad application potential for fingermark detection.