Super paramagnetic core-shells anchored onto silica grafted with C8/NH2 nano-particles for ultrasound-assisted magnetic solid phase extraction of imipramine and desipramine from plasma.

In current work the Fe3O4 magnetic nano-particles anchored to core-shells of SiO2 which grafted by C8/NH2 dual mixed groups, have been synthesized. The magnetic nano-particles were characterized by scanning electron microscopy, X-ray diffraction spectroscopy, and zeta-potential reader. The resulted nano-particles have spherical structure with diameters in the range of 105 to 110 nm. A magnetic solid phase extraction method was developed for extraction of imipramine and desipramine from human plasma samples under ultrasonic conditions by using of prepared NPs as sorbent. The MNPs were dispersion in plasma under sonicated conditions, accumulated by an external magnetic field and washed with Briton-Robinson buffer-acetonitrile solution (0.05 mol l-1, pH = 5, 10%V/V). The drugs were removed by methanol and quantified by gas chromatography. The calibration curves (correlation coefficient > 0.99) for IMP and DES were linear in the concentration range of 0.005 to 5 and 0.01 to 4 μg ml-1, respectively. The LOD, LOQ, intra and inter-day precision values were measured too. The proposed Fe3O4/SiO2/C8/NH2 MNPs could be applied for 3.0 times.