Improvement of solid phase microextraction fiber assembly and interface for liquid chromatography.

Area of Science:

• Analytical Chemistry
• Chromatography
• Sample Preparation

Background:

• Traditional solid-phase microextraction (SPME) fiber assemblies and SPME-liquid chromatography (LC) interfaces suffer from solvent leaks and fiber coating damage.
• These limitations hinder the applicability and reliability of SPME-LC for routine analysis.

Purpose of the Study:

• To develop and evaluate modified SPME fiber assemblies and SPME-LC interfaces for improved performance.
• To address drawbacks such as solvent leakage and fiber coating damage in existing SPME-LC systems.

Main Methods:

• Commercial SPME fiber assemblies were modified using a polyacrylonitrile (PAN)/C18 bonded fused silica fiber and a solid nitinol rod.
• The SPME-LC interface ferrule's inner diameter was enlarged to accommodate the nitinol rod, protecting the fiber coating.
• The system's robustness and reliability were assessed through pressure tests, desorption optimization, peak shape analysis, carryover evaluation, linearity, precision, and limit of detection (LOD) using polycyclic aromatic hydrocarbons (PAHs).

Main Results:

• The modified SPME fiber assembly and SPME-LC interface demonstrated robustness and reliability in performance evaluations.
• The enhanced design effectively prevented solvent leaks and protected the fiber coating from damage during operation.
• A novel sealing mechanism using a poly(ether ether ketone) (PEEK) fitting was developed and tested for manual operation.

Conclusions:

• The improved SPME fiber assembly and SPME-LC interface overcome critical limitations of current technologies.
• This enhanced system offers a robust and reliable solution for SPME-LC applications, particularly for analyzing PAHs.
• The developed device is suitable for manual use, expanding the practical applicability of SPME-LC.