Preparation, characterization and application of N-methylene phosphonic acid chitosan grafted magnesia-zirconia stationary phase.

A hydrophilic stationary phase (SP) was prepared through grafting N-methylene phosphonic acid chitosan on magnesia-zirconia particles (P-CTS-MgO-ZrO2) via Lewis acid-base interaction. The resulting material was characterized by thermogravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscope and nitrogen adsorption analysis. The chromatographic performance of P-CTS-MgO-ZrO2 was systemically evaluated by studying effect of acetonitrile content, pH and buffer concentration in the mobile phase. The results demonstrated that the novel SP provided hydrophilic, electrostatic-repulsion and ion-exchange interactions. Compared to the bare MgO-ZrO2, P-CTS-MgO-ZrO2 exhibited superior peak shape, reasonable resolution and reduced analysis time in separation of basic analytes. Besides, remarkable resolving power of acids, i.e. six non-steroidal anti-inflammatory drugs which failed to be eluted from the bare MgO-ZrO2, was obtained with the theoretical plate number (N/m) of 4653-31313, asymmetry factor <1.21 and the resolution of 1.6-3.4. Finally, P-CTS-MgO-ZrO2 SP was applied to separate monosaccharides, phospholipids and peptides. P-CTS-MgO-ZrO2 was a promising hydrophilic SP for wide applications.