Making criminals leave chemical fingerprints

Scientists in Brazil have shown that luminescent lanthanide tags can be added to ammunition to enable visual identification of gunshot residue at crime scenes, and even on a shooter’s hands, using an ultraviolet lamp.

Scanning electron microscopy-energy dispersive spectroscopy analysis is currently used to identify some types of gunshot residue, but environmental and occupational contamination can give false negatives. The method is also time-consuming and limited by the need to obtain adequate sample quantities. Another problem is that lead-free ammunition is now coming into use to avoid lead pollution and its resulting impact on human health. (The blood level of lead in shooting instructors, for example, is near the limit set out by the National Institute for Occupational Safety and Health of 60µg lead per 100g blood.) But, this ammunition cannot be unequivocally identified, as the techniques used rely on identifying lead as a characteristic compound in gunshot residue.

Luminescent lanthanide-doped ZnAl2O4 added to lead-free ammunition to provide a way to identify lead-free gunshot residue (GSR)

 To read the full article please vist Chemistry World.

ZnAl2O4-based luminescent marker for gunshot residue identification and ammunition traceability
M. A. Melo Lucena ,  G. F. de Sá ,  M. O. Rodrigues ,  S. Alves ,  M. Talhavini and I. T. Weber
Anal. Methods, 2013, Advance Article
DOI: 10.1039/C2AY25535A

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)