Cooling/heating-assisted headspace solid-phase microextraction of polycyclic aromatic hydrocarbons from contaminated...

Area of Science:

• Analytical Chemistry
• Environmental Science

Background:

• Solid-phase microextraction (SPME) is a widely used technique for analyzing volatile and semi-volatile compounds.
• Conventional SPME methods often require extensive sample pretreatment and lack the ability to create significant temperature gradients between the fiber and the sample matrix.
• Analyzing polycyclic aromatic hydrocarbons (PAHs) in complex solid matrices like soil presents challenges due to their low volatility and the matrix complexity.

Purpose of the Study:

• To develop and evaluate a simple, low-cost, and effective cooling/heating-assisted headspace solid-phase microextraction (CHA-HS-SPME) device.
• To enhance the extraction efficiency of volatile and semi-volatile species from complex solid matrices.
• To optimize the CHA-HS-SPME device for the extraction and determination of polycyclic aromatic hydrocarbons (PAHs) in contaminated soils.

Main Methods:

• Fabrication of a CHA-HS-SPME device capable of directly cooling the fiber and heating the sample matrix simultaneously.
• Optimization of experimental parameters for device fabrication, extraction, and determination of PAHs.
• Coupling the CHA-HS-SPME device with Gas Chromatography-Flame Ionization Detection (GC-FID) for analysis.
• Application of the method to extract and determine PAHs in contaminated soil samples without prior sample pretreatment.

Main Results:

• The CHA-HS-SPME device successfully cooled commercial and handmade fibers, enabling effective tapping of volatile and semi-volatile species.
• The system created large temperature gaps (up to 200 °C) between the fiber and the sample matrix, improving extraction efficiency.
• The proposed CHA-HS-SPME-GC-FID method was successfully applied to extract and determine PAHs in contaminated soils with no sample pretreatment.
• Results obtained by the proposed method showed good agreement with a validated method.

Conclusions:

• The developed CHA-HS-SPME device is a simple, low-cost, and effective tool for analyzing volatile and semi-volatile compounds in complex solid matrices.
• The ability to create significant temperature gradients enhances extraction efficiency and reduces the need for sample pretreatment.
• The CHA-HS-SPME-GC-FID method provides a reliable and efficient approach for the determination of PAHs in environmental samples like contaminated soils.