Interfacing an ion mobility spectrometry based explosive trace detector to a triple quadrupole mass spectrometer.

Area of Science:

• Analytical Chemistry
• Spectroscopy

Background:

• Commercial-off-the-shelf (COTS) ion mobility spectrometry (IMS) based explosive trace detector (ETD) systems have limitations in characterizing their intrinsic ion chemistry.
• Understanding gas-phase ion chemistry is crucial for enhancing the operational effectiveness of ETD equipment.

Purpose of the Study:

• To develop and validate a platform for characterizing the gas-phase ion chemistry of COTS IMS-based ETD equipment.
• To improve the operational capabilities of COTS ETD systems through a deeper understanding of their ion chemistry.

Main Methods:

• Interfacing COTS IMS-ETD hardware with an AB/SCIEX API 2000 triple quadrupole mass spectrometer using custom-fabricated components.
• Modifying the mass spectrometer to optimize ion transmission and enable mobility spectrum acquisition.
• Acquiring mass spectra, tandem mass spectra, and mass-selected ion mobility spectra for explosive standards.

Main Results:

• Successfully obtained mass and tandem mass spectra in continuous ion flow and selected mobility monitoring modes.
• Measured mass-selected ion mobility spectra for 2,4,6-trinitrotoluene (TNT), identifying the product ion as [TNT - H](-).
• Determined the predominant collision-induced dissociation pathway for [TNT - H](-) and its reduced mobility value (1.54 cm(2)V(-1)s(-1)) using 1 ng samples with 37 resolving power.

Conclusions:

• The developed COTS-ETD/API 2000 configuration is effective for characterizing gas-phase ion chemistry.
• This platform provides insights into the ion chemistry of COTS ETD equipment, advancing their operational effectiveness.
• The study demonstrates the potential for detailed analysis of explosive compounds at low sample amounts.