The analysis of nitrate explosive vapour samples using Lab-on-a-chip instrumentation

Area of Science:

• Analytical Chemistry
• Forensic Science

Background:

• Explosives detection is critical for homeland security.
• Existing methods for explosives analysis can be cumbersome.
• There is a need for portable and efficient explosives detection systems.

Purpose of the Study:

• To evaluate a Lab-On-a-Chip (LOC) instrument for explosive vapor analysis.
• To develop a simple method for collecting explosive vapor residues.
• To establish a foundation for a portable, passive explosives detection instrument.

Main Methods:

• Developed a method using glass vials and filter paper for explosive vapor collection.
• Utilized acetone to facilitate explosive compound evaporation.
• Analyzed collected residues on a commercial LOC instrument.
• Tested target explosives: 1,3,5-Trinitrobenzene (TNB), 2,4,6-Trinitrotoluene (TNT), and Tetryl.

Main Results:

• Successfully separated, detected, and identified TNB, TNT, and Tetryl in vapor samples.
• Achieved limits of detection as low as 6.03 ng for TNB in vapor analysis.
• Demonstrated average recovery rates of 29% (Tetryl), 47% (TNB), and 75% (TNT).
• Determined optimal vaporization temperature between 40°C and 80°C.

Conclusions:

• The developed filter paper collection method is effective for explosive vapor residues.
• LOC instrument analysis of these residues is feasible and efficient.
• This approach represents a promising alternative for portable explosives detection in air samples.