Development of fingermarks on Latex gloves: The solution to a challenging surface

Area of Science:

• Forensic Science
• Trace Evidence Analysis
• Biochemistry

Background:

• Latex gloves are crucial forensic evidence, containing fingerprints and DNA.
• Standard fingermark development techniques often yield poor results on latex gloves.
• Glove manufacturing changes, including polymer coatings, complicate analysis.

Purpose of the Study:

• To evaluate the effectiveness of Ninhydrin-HFE and superglue fuming/crystal violet dyeing for fingermark development on latex gloves.
• To identify optimal methods for enhancing fingermark visibility on this challenging substrate.
• To understand the chemical and structural properties influencing fingermark development on latex.

Main Methods:

• Tested Ninhydrin-HFE and superglue fuming/crystal violet dyeing on 100 latex gloves from 25 donors.
• Examined the porous vs. non-porous characteristics of glove interiors.
• Utilized Scanning Electron Microscopy (SEM) to assess solvent effects on glove coatings.

Main Results:

• Ninhydrin-HFE significantly outperformed superglue fuming for fingermark development.
• Results suggest the interior of latex gloves behaves as a porous surface.
• The choice of solvent is critical; HFE-7100 preserved the inner polymer coating, unlike petroleum ether.

Conclusions:

• Ninhydrin-HFE is a superior method for developing fingermarks on latex gloves.
• The success of fingermark development depends on the solvent-sensitive structure of the gloves.
• HFE-7100 offers an effective and compatible solvent system for latex glove analysis.