The application of novel 1.7 μm ethylene bridged hybrid particles for hydrophilic interaction chromatography

An un-derivatized 1.7 mu m ethylene bridged hybrid (BEH) particle was evaluated for its utility in retaining polar species in hydrophilic interaction chromatography (HILIC), and was compared to a 3 mu m un-derivatized silica material. Retentivity as a function of mobile phase pH, polar modifier and ACN content was examined. Also, the efficiency of the two particle substrates was compared by plotting HETP vs. linear velocity. Improved chemical resistance of the un-derivatized BEH particle was compared to un-derivatized silica at pH 5, demonstrating no performance deterioration over the course of 2000 injections for the BEH particle, while the silica particle deteriorated rapidly after 800 injections. Lastly, ESI-MS sensitivity as a function of particle size and separation mode was demonstrated. A 2.2 to 4.7-times higher ESI-MS response was observed on the 1.7 mu m particle compared to the 3 mu m particle, whereas a 5.6 to 8.8-times higher ESI-MS response was observed using HILIC as when compared to traditional RP chromatography.