Laser desorption sample transfer for gas chromatography/mass spectrometry
Copyright © 2015 John Wiley & Sons, Ltd. Rationale Ambient mass spectrometry can detect small molecules directly, but complex mixtures can be a challenge. We have developed a method that incorporates small molecule separation based on laser desorption with capture on a solid-phase microextraction (SPME) fiber for injection into a gas chromatography/mass spectrometry (GC/MS) system. Methods Samples on a metal target were desorbed by a 3 μm mid-infrared laser focused to a 250 μm spot and 1.2 mJ pulse energy. The desorbed material was aspirated into a metal tube suspended 1 mm above the laser spot and captured on a SPME fiber. The collected material was injected into a GC/MS instrument for analysis. Results We have developed a versatile approach for ambient laser desorption sampling onto SPME for GC/MS analysis. The performance of the laser desorption SPME capture GC/MS system was demonstrated for small molecule standards, a mixture of nitroaromatic explosives, and collected cigarette smoke. Conclusions The utility of ambient laser desorption sampling onto SPME for GC/MS was demonstrated. The performance of the method was evaluated by preparing calibration standards of caffeine over a range from 200 to 1000 ng. Laser desorption ambient sampling of complex mixtures was accomplished using SPME GC/MS.
Publication Source (Journal or Book title)
Rapid Communications in Mass Spectrometry
Seneviratne, C., Ghorai, S., & Murray, K. (2016). Laser desorption sample transfer for gas chromatography/mass spectrometry. Rapid Communications in Mass Spectrometry, 30 (1), 89-94. https://doi.org/10.1002/rcm.7419