Applicability of new configuration of open tubular solid phase microextraction for determination of free (unconjugated) testosterone esters by gas chromatography with barrier ionization discharge detector

The methodology has been developed for analyzing testosterone esters in urine by gas chromatography with a barrier ionization discharge (GC-BID) detector for anti-doping analysis. For sample preparation, poly-dimethylsiloxane (PDMS) was used as a trapping polymer in the new configuration of an open tube trapping solid-phase microextraction (OTT-SPME). The new device developed by this research group was called Intra Tube Flux Extraction (IT-FEX-SPME). The performance of the IT-FEX-SPME-GC-BID method was validated concerning extraction kinetics, sensitivity: the limit of detection (LOD 0.5-0.8 ng mL-1) and the limit of quantification (LOQ 1.5-2.4 ng mL-1), repeatability (<8%), reproducibility <7.5 %), linearity (R2>0.991), re-covery (mean 102.44 %), and stability (<30 %). The values obtained are acceptable, and the results showed the potentiality of the methodology to control testosterone ester doping. The qualitative performance of the pro-posed method is compared with those that use a mass spectrometer as a detector.