Palladium-coated stainless-steel wire as a solid-phase microextraction fiber

Area of Science:

• Analytical Chemistry
• Environmental Science
• Materials Science

Background:

• Accurate detection of environmental contaminants like polycyclic aromatic hydrocarbons (PAHs) and phthalate esters (PEs) is crucial for public health.
• Traditional methods for analyzing these compounds can be time-consuming and require large sample volumes.
• Solid-phase microextraction (SPME) offers a more efficient alternative for sample preparation.

Purpose of the Study:

• To develop a novel palladium-based solid-phase microextraction (SPME) coating for the simultaneous extraction of PAHs and PEs from aqueous samples.
• To optimize the fabrication and extraction conditions for enhanced analytical performance.
• To evaluate the method's efficiency, sensitivity, and applicability to real-world environmental samples.

Main Methods:

• Fabrication of a palladium coating on a stainless-steel wire using an in situ oxidation-reduction process.
• Optimization of palladium coating preparation (reaction time, PdCl2 and HCl concentrations).
• Direct immersion SPME of PAHs and PEs from aqueous samples, followed by thermal desorption and gas chromatography analysis.
• Investigation of extraction and desorption parameters to maximize efficiency.

Main Results:

• The fabricated palladium coating had a microscaled surface with a thickness of approximately 2 μm.
• Optimized conditions yielded good linearity (correlation coefficients 0.9908–0.9990) for both analyte classes.
• Achieved low limits of detection (0.05–0.10 μg/L for PAHs, 0.3 μg/L for PEs) and high recoveries (97.1–121% for PAHs, 89.1–108% for PEs) in real samples.
• Satisfactory intra- and interday reproducibility was demonstrated.

Conclusions:

• The novel palladium-coated SPME fiber is effective for the sensitive and efficient extraction of PAHs and PEs from aqueous matrices.
• The method demonstrates excellent linearity, low detection limits, and high recovery rates, making it suitable for environmental monitoring.
• The simple fabrication process and robust performance highlight the potential of this material for trace analysis applications.