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Carboxylic acid functional group analysis using constant neutral loss scanning-mass spectrometry
Julien Dron1, Gregory Eyglunent, Brice Temime-Roussel
1Laboratoire de Chimie et Environnement, Marseille Universités (case 29), 3 place Victor Hugo, 13331 Marseille Cedex 3, France. julien.dron@up.univ-mrs.fr
Analytica Chimica Acta
|November 21, 2007
Summary
This study introduces a novel method for quantifying carboxylic acid groups using tandem mass spectrometry. The technique offers precise measurements in complex environmental samples, marking a significant advancement in chemical analysis.
Area of Science:
- Analytical Chemistry
- Environmental Science
- Mass Spectrometry
Background:
- Carboxylic functional groups are crucial in various chemical and biological processes.
- Accurate determination of carboxylic acids is essential for environmental monitoring and chemical characterization.
- Existing methods may face limitations in sensitivity or applicability to complex matrices.
Purpose of the Study:
- To develop and validate a new analytical technique for the quantitative determination of carboxylic functional groups.
- To utilize atmospheric pressure chemical ionization-mass spectrometry (APCI-MS/MS) in constant neutral loss scanning (CNLS) mode for this purpose.
- To demonstrate the method's applicability to environmental samples, specifically atmospheric aerosols.
Main Methods:
- Derivatization of carboxylic groups to methyl esters using BF3/methanol.
- Direct injection of the reaction mixture into the APCI source.
- Monitoring the constant neutral loss of methanol (32 amu) in APCI-MS/MS operated in CNLS mode.
- Statistical analysis of results from reference mixtures containing 31 carboxylic acids.
Main Results:
- The developed method achieved quantitative functional group measurements with relative standard deviations below 15%.
- A low detection limit of 0.005 mmol L(-1) was established for carboxylic acids.
- The technique was successfully applied to determine carboxylic acid concentrations in atmospheric aerosol samples.
- This represents the first application of tandem mass spectrometry for functional group analysis.
Conclusions:
- The novel APCI-MS/MS CNLS method provides a reliable and sensitive approach for carboxylic group determination.
- The technique is suitable for analyzing complex environmental matrices, offering new possibilities in chemical characterization.
- This advancement enhances our understanding of chemical processes within environmental systems.
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