Metal organic framework-801 based magnetic solid-phase extraction and its application in analysis of preterm labor treatment drugs

A novel magnetic solid-phase extraction (MSPE) method based on metal organic framework-801 (MOF-801) modified magnetic nanoparticles (noted as PEI-MNPs@MOF-801) was successfully prepared for the extraction of preterm labor treatment drugs (including indometacin, acemetacin and sulindac) from human plasma sample. MOF-801, a new kind of porous coordination polymer composed of Zr⁴⁺ and fumaric acid, was modified on the surface of synthesized polyethyleneimine magnetic nanoparticles (PEI-MNPs) through amidation reaction. The obtained PEI-MNPs@MOF-801 was characterized with Fourier-transformed infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and transmission electron microscopy. A MSPE-HPLC-UV method was developed by coupling PEI-MNPs@MOF-801 with HPLC system. Several parameters that affect the extraction efficiency including acetonitrile content, NaCl content, extraction time and sample volume were investigated. Under optimum conditions, the proposed MSPE-HPLC-UV method showed high extraction efficiency (enrichment factors between 96-118), good linearity with R ≥ 0.9987, excellent reproducibility (RSD ≤ 4.30 %) and low limits of detection in the range of 0.03-0.05 ng/mL. This method was also successfully applied to the extraction of indometacin, acemetacin and sulindac in human plasma samples and good recoveries were obtained.