Cross-linker effects on the separation efficiency on (poly)methacrylate capillary monolithic columns. Part II. Aqueous normal-phase liquid chromatography

The Effects of the Column Length on the Efficiency of Capillary Zwitterionic Organic Polymer Monolithic Columns in HILIC Chromatography

“…In a recent study, we investigated the column-to-column reproducibility by comparing the retention data and bandwidths of various samples on nine different columns, prepared individually. The retention data demonstrated good repeatability (0.5-0.6 % for the nine DiEDMA columns and 0.6-1.3 % for the nine BIGDMA columns) [11]. The same results can be expected for gradually shortened columns preparing by subsequent cutting of short pieces.…”

“…However, the H-u plots (Eq. 2) are more shallow (show lower C-terms, characterizing less efficiency at higher flow rates of the mobile phase) in comparison to the ZIC-HILIC column, especially for weakly polar and non-polar samples (toluene, phenol [11].…”

“…Replacing the original ethylene dimethacrylate (EDMA) crosslinking monomer by crosslinking monomers with higher polarity and size, we significantly improved the efficiency of the capillary monolithic columns [11]. Capillary columns prepared by radical polymerization of N,N-dimethyl-N-methacryloxyethyl-N- (3-sulfopropyl) ammonium betaine as a zwitterionic functional monomer and bisphenol A glycerolate dimethacrylate as a crosslinking monomer were successfully applied in comprehensive two-dimensional HPLC [12].…”

Monolithic capillary columns based on pentaerythritol acrylates for molecular‐size‐based separations of synthetic polymers

“…The specific structure of the monomers resulted in monoliths with an increased microporosity and correspondingly increased contribution of SEC mechanism to polymer separation. Furthermore, the resolution achieved in the separation of the polystyrene standards considerably exceeds the values reported in the literature for similar monolithic columns [22,24]. The optimal structure of all monoliths regardless of the type of monomer used in preparation of monoliths was achieved using porogen consisting of nonanol as a poor solvent.…”

“…Using light scattering detection (LSD), it would be possible to distinguish between the cases, but detection cell volume of currently LSD incompatible with capillary columns used in the study. Anyway, the monolithic column prepared in this work can separate twice as much polystyrene standards in one run as the counterparts reported in the literature [22,24] and their almost linear calibration curves makes them attractive for the polymer analysis over broad range of molar mass.…”