Organic ion imaging using tandem mass spectrometry.

Area of Science:

• Analytical Chemistry
• Materials Science
• Spectroscopy

Background:

• Secondary ion mass spectrometry (SIMS) is crucial for surface analysis.
• Isobaric interference can limit the specificity and resolution of SIMS imaging.
• Tandem mass spectrometry (MS/MS) offers enhanced selectivity for molecular identification.

Purpose of the Study:

• To interface a triple-quadrupole mass spectrometer with a wide-angle secondary ion microprobe.
• To demonstrate the capability of MS/MS for analyzing organic analytes in complex matrices.
• To improve the quality and specificity of secondary ion microprobe imaging.

Main Methods:

• Interfacing a triple-quadrupole mass spectrometer with a wide-angle secondary ion microprobe.
• Utilizing tandem mass spectrometry (MS/MS) for selective ion detection.
• Analyzing inhomogeneous mixtures of glycerol, KCl, and asparagine on aluminum targets.
• Comparing imaging results from secondary ion intensity alone versus MS/MS-enhanced imaging.

Main Results:

• The combined instrument successfully acquired data to determine targeted organic analyte distribution.
• MS/MS significantly improved image quality by overcoming isobaric interferences.
• Demonstrated selectivity in analyzing glycerol, KCl, and asparagine in the presence of 133Cs+ ions.

Conclusions:

• The interfaced system provides enhanced selectivity and imaging capabilities for organic analysis.
• MS/MS is a powerful tool for resolving isobaric interferences in secondary ion microprobe analysis.
• This approach enables more accurate mapping of organic analyte distributions in complex samples.