| A perhydro-26-membered hexaazamacrocycle-based silica (L1GlySil) stationary phase for high-performance liquid chromatography (HPLC) was prepared. The structure of new material was characterized by infrared spectroscopy, elemental analysis, thermogravimetric analysis, nuclear magnetic resonance (NMR). The chromatographic performance and retention mechanism of the new phase were evaluated by using different solute probes including aromatic compounds, organophosphorus pesticides, carbamate pesticides, nucleotides and phenols. The content of methanol in the mobile phase resulted in the change of the selectivity of L1GlySil for five aromatic compounds and five cabamate pesticides. The results showed that the retentions of analytes on L1GlySil were involved in multiple mechanisms including hydrophobic, hydrogen bonding, dipole-dipole interactions and acid-base equilibrium. The existence of multiple mechanisms made the new phase be operated in reversed-phase (RP) and normal-phase (NP) modes. Under NP or RP mode, the selected analytes were separated effectively on L1GlySil column.A silica gel bonded stationary phase based on N-Allylpyridine chloride ionic liquid was prepared for HPLC and was characterized by infrared spectrum and elemental analysis. Sil-Apy was evaluated by using different solute probes including aromatic compounds, phenols, nucleotides, carbamate pesticides and organophosphorus pesticides. The effects of methanol content in mobile phase, pH value and concentrations of phosphate buffer solution on the retention factors (k) and selectivity (α) of the above analytes were investigated. Compared with C18 column, the new stationary phase interacted with analytes by multiple mechanisms including hydrophobic, hydrogen bonding,π-πand electrostatic interactions. Aromatic compounds, phenols, nucleotides, carbamate pesticides and organophosphorus pesticides can be separated effectively on Sil-Apy column.A silica gel bonded stationary phase based on 1-methyl-3-crylic acid iminazole chloride ionic liquid was prepared for HPLC and was characterized by infrared spectrum and elemental analysis. Aromatic compounds, phenols, carbamate pesticides and organophosphorus pesticides were elected as analytes to evaluate the chromatographic performance of Sil-MImAA. Under certain chromatographic condition, all analytes were separated effectively on Sil-MImAA. Compare with C18 column, the selectivity of carbamate pesticides and organophosphorus pesticides was discriminating, the results indicated that charge transfer,π-πand electrostatic interactions. The interactions enhanced rentention of analytes on Sil-MImAA. Multiple mechanisms involved between analytes and Sil-MImAA.
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