Carbon fibers modified with polypyrrole for headspace solid phase microextraction of trace amounts of 2-pentyl furan from breath samples

Abstract

This study introduces micrometric carbon strands as a suitable fiber for headspace solid phase microextraction. Compared to previous supports, carbon fibers have mechanical flexibility, wide thermal expansion, and a large surface area, which is an important factor in headspace solid phase microextraction. The electrophoretic technique was applied to modify the surface of stainless steel and carbon fibers with polypyrrole. Modified carbon fibers were used for extraction of 2-pentylfuran (2-PF) as a model analyte from patients’ breath and coffee samples. 2-PF belongs to the furan family, which was suggested as a biomarker for Aspergillus fumigatus and was classified as a possible carcinogen. 2-PF can be found in many heat-processed foods and drinks. The separation and detection of the analyte was performed by gas chromatography coupled to mass spectrometry. The effective factors in the extraction performance of the analyte by carbon fiber supports were investigated and optimized. Under optimized extraction conditions (temperature, 20 °C; time, 15 min; desorption temperature, 200 °C; desorption time, 2 min; salt concentration, 10% w/v; and stirring rate, 700 rpm), the limit of detection was calculated as 0.05 ng mL−1, whereas repeatability and fiber-to-fiber reproducibility (RSD %) was found to be in the range of 3.2–4.1%. The experimental results showed that the proposed fiber had greater extraction performance for 2-pentylfuran.