Solid-phase microextraction with temperature-programmed desorption for the analysis of iodination disinfection...

Area of Science:

• Environmental Chemistry
• Analytical Chemistry

Background:

• Disinfection byproducts (DBPs) are formed during water treatment.
• Accurate quantification of DBPs is crucial for public health and environmental safety.

Purpose of the Study:

• To develop and validate a novel analytical method for determining chlorination and iodination disinfection byproducts.
• To optimize solid-phase microextraction (SPME) conditions for efficient and non-degradative analyte transfer.

Main Methods:

• Development of a solvent-free sample preparation technique using SPME coupled with gas chromatography-mass spectrometry (GC/MS) and gas chromatography-electron capture detection (GC/ECD).
• Evaluation of isothermal and temperature-programmed thermal desorptions (TPD) to prevent analyte degradation.
• Optimization of TPD parameters (temperature ramp, injection port type) for analytes with varying volatilities and thermal stabilities.

Main Results:

• A temperature-programmed desorption (TPD) method (120-200°C at 5°C/min or 150-200°C at 25°C/min) efficiently transferred analytes without thermal degradation.
• The SPME-TPD method demonstrated linearity over 2-3 orders of magnitude with submicrogram per liter detection limits using GC/ECD.
• Method performance, including precision and detection limits for trihalomethanes, was comparable to EPA Method 551.
• Extraction efficiencies were unaffected by common water matrix components like soap, sodium iodide, and sodium thiosulfate.

Conclusions:

• The developed SPME-TPD technique provides a sensitive, rapid, and solvent-free approach for analyzing chlorination and iodination disinfection byproducts.
• This method is suitable for quantifying trace levels of DBPs, including iodoform, in various water matrices.
• The technique offers a viable alternative to existing methods for DBP analysis in environmental monitoring and water quality assessment.