Comparison of Testosterone Extraction from Human Plasma Using MOFs (MIL-53(Al) and ZIF-8)-Based D-µ-SPE Coupled to HPLC–UV

A novel technique utilizing metal–organic frameworks (MOFs), namely MIL-53(Al) and ZIF-8, has been developed for the extraction of testosterone from human plasma through dispersive micro-solid phase extraction (D-µ-SPE or DMSPE). The synthesized MOFs were subjected to characterization via Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), and scanning electron microscopy (SEM). The parameters affecting the extraction were optimized by response surface methodology (RSM). The optimal extraction conditions were determined to be 15 min for contact time, 1 mg for MIL-53(Al) amount, and 0.23% (w/v) for NaCl concentration. For ZIF-8, a contact time of 22 min, a sorbent amount of 5.4 mg, and a salt concentration of 0.34% (w/v) were obtained. Batch absorption studies were conducted to find appropriate kinetic and isotherm models. The results indicated that while testosterone absorption was favorable in both cases, MIL-53 (Al) had a higher absorption capacity than ZIF-8. Finally, the proposed method was subjected to analytical validation for determination of testosterone in plasma samples. Good analytical performance was achieved, including a dynamic range of 0.05–1 µg/mL using each of the sorbents. The precision (expressed as the relative standard deviation (RSD)) and accuracy (expressed as the percentage error) of the method for testosterone and MIL-53(Al) were found to be 3.40% and 2.79%, respectively, while for testosterone and ZIF-8, they were 4.24% and 4.22%, respectively. The method effectively extracted 97% and 96% of testosterone from spiked plasma samples using MIL-53(Al) and ZIF-8, respectively.