Disposable solid-phase microextraction fiber coupled with gas chromatography-mass spectrometry for complex matrix analysis

Abstract

Recent developments of solid-phase microextraction (SPME) in biological and environmental analysis calls for robust and low-cost fibers that are prone to batch preparation with good reproducibility. However, the expensive commercial fibers and low reproducible home-made fibers cannot fully cater these requirements. In the present study, an extremely low-cost (less than one dollar) SPME fiber with good intra-fiber (RSDs% ≤ 1.6%, n = 6) and inter-fiber reproducibility (RSDs% ≤ 6.2%, n = 6) was prepared by mounting a piece of commercially available polydimethylsiloxane (PDMS) tubing on a stainless steel wire with epoxy glue. This configuration was stable for more than 100 extraction/thermal desorption cycles. In addition, compared with previously used thicker PDMS fiber, the capability of direct thermal desorption in gas chromatograph of the present fiber not only simplified the sample preparation process but also enhanced the analysis sensitivity. Excellent inter-fiber reproducibility and low cost even made the fiber disposable when used in complex matrices.