Dipyridine modified silica—A novel multi-interaction stationary phase for high performance liquid chromatography

A novel multi-interaction stationary phase based on 4,4′-dipyridine modified silica was synthesized and characterized, by infrared spectra, X-ray photoelectron spectroscopy and elemental analysis. Mechanism involved in the chromatographic separation is the multi-interaction including π–π, hydrophobic, hydrogen-bonding, electrostatic and anion-exchange interactions. Based on these interactions, polycyclic aromatic hydrocarbons and phenols were successfully separated respectively in reversed-phase chromatography; inorganic and organic anions were also separated individually in anion-exchange chromatography by using the same column. Furthermore, the simultaneous separation of neutral organics, inorganic and organic anions was obtained on this stationary phase with the appropriate mobile phase. Therefore, such stationary phase has the characteristics of multi-interaction mechanism and multi-modal separation, and has potential application on complex samples.