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Energy-Resolved In-Source Collison-Induced Dissociation for Isomer Discrimination
Matthew J Carlo1, Andie L M Nanney1, Amanda L Patrick1
1Department of Chemistry, Mississippi State University, Mississippi State, Mississippi 39762, United States.
Journal of the American Society for Mass Spectrometry
|July 17, 2024
Summary
In-source collision-induced dissociation (IS-CID) offers a way to differentiate isomers using energy-resolved measurements, even on simpler mass spectrometers. This method enhances selectivity without requiring complex additional equipment.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry
- Separation Science
Background:
- Mass spectrometry is crucial for analyte analysis but struggles with isomer differentiation.
- Tandem mass spectrometry and energy-resolved measurements improve selectivity but require specialized instruments.
- Compact and affordable mass spectrometers often lack capabilities for advanced dissociation experiments.
Purpose of the Study:
- To investigate energy-resolved in-source collision-induced dissociation (IS-CID) as a method for isomer differentiation.
- To compare energy-resolved appearance curves from IS-CID with those from traditional tandem mass spectrometry.
- To evaluate IS-CID's potential for differentiating isomers with similar dissociation patterns and explore implementation considerations.
Main Methods:
- Utilized in-source collision-induced dissociation (IS-CID) on single-stage mass spectrometers.
- Measured energy-resolved appearance curves using IS-CID.
- Compared IS-CID results with data from a quadrupole time-of-flight instrument employing true tandem mass spectrometry.
- Assessed the ability of IS-CID to differentiate isomers and isobar sets.
Main Results:
- Energy-resolved appearance curves obtained via IS-CID show analytical potential comparable to tandem mass spectrometry.
- IS-CID effectively differentiates isomers and isobar sets, including those with similar fragmentation patterns.
- The study explored analytical considerations for method development and implementation of IS-CID.
Conclusions:
- Energy-resolved IS-CID provides a viable alternative for isomer differentiation on mass spectrometers lacking advanced capabilities.
- This approach broadens the accessibility of enhanced selectivity in mass spectrometry.
- IS-CID presents a promising technique for future method development in various applications, including field-portable devices and educational settings.
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