Volatile organic analysis by direct aqueous injection.

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Chromatography

Background:

• Accurate quantification of volatile organic analytes (VOAs) is crucial for environmental monitoring.
• Traditional methods may require extensive sample preparation, increasing analysis time and cost.

Purpose of the Study:

• To evaluate the efficacy of direct aqueous injection (DAI) coupled with gas chromatography-ion trap mass spectrometry for analyzing VOAs.
• To compare the precision and sensitivity of single-ion versus triple-ion quantitation methods.

Main Methods:

• Direct aqueous injection of samples into a gas chromatograph with a fused-silica capillary column.
• Analysis using full-scan ion trap mass spectral detection.
• Quantification via internal standardization, comparing single-ion and triple-ion response curves.

Main Results:

• Triple-ion quantitation demonstrated higher sensitivity and precision than single-ion quantitation for VOAs.
• High correlation coefficients (r(2) > 0.990 for 76% of curves) were achieved.
• Successful analysis of an environmental sample in 12 minutes, detecting benzene and chlorobenzene.

Conclusions:

• Direct aqueous injection gas chromatography is a feasible technique for rapid environmental screening of VOAs.
• The method shows potential for expansion to include higher boiling point compounds, such as chlorinated benzenes.