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Preparation and Application of a New Bacterial Biosensor for the Presumptive Detection of Gunshot Residue
Published on: May 9, 2019
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Evaluation of Total Nitrite Pattern Visualization as an Improved Method for Gunshot Residue Detection and its
Jason Berger1, Colin Upton1, Elyah Springer1
1Police Laboratory, New York City Police Department, 15014 Jamaica Ave, Jamaica, NY, 11432.
Journal of Forensic Sciences
|April 24, 2018
Summary
This study enhances Total Nitrite Pattern Visualization (TNV) for gunshot residue analysis. The improved method rapidly and effectively detects nitrite residues, aiding in gunshot distance determination.
Area of Science:
- Forensic Science
- Analytical Chemistry
Background:
- Nitrite residue visualization is crucial for gunshot distance determination.
- The Modified Griess Test (MGT) is limited by unstable residues and detection of only partially burned gunpowder.
Purpose of the Study:
- To streamline and enhance Total Nitrite Pattern Visualization (TNV) techniques for casework.
- To reduce processing time and improve effectiveness on blood-soiled samples.
Main Methods:
- Modification of existing TNV techniques involving alkaline hydrolysis.
- Streamlining the procedure to decrease analysis time from 1 hour to 5 minutes.
- Testing enhanced TNV effectiveness on blood-soiled samples.
Main Results:
- The modified TNV method significantly improved the detection of nitrite residues.
- The procedure was made more efficient and effective, especially on blood-soiled samples.
- Reduced analysis time from 1 hour to 5 minutes without sacrificing efficiency.
Conclusions:
- The enhanced TNV method offers a significant improvement for detecting nitrite residues in forensic casework.
- This technique aids in the determination of muzzle-to-target distance more effectively and efficiently.
- The streamlined TNV method is valuable for analyzing unburned gunpowder particles and improving residue visualization.
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