Preparation of normal‐phase HPLC stationary phase based on monodisperse hydrophilic polymeric beads and their application

Abstract

The monodisperse, 5.0 lm hydrophilic macroporous poly(glycidymethacrylate-co-ethylenedimethacrylate) beads were first prepared based on monosized linear poly(glycidylmethacrylate) beads as seed by using a single-step swelling and polymerization method. The seed beads prepared by dispersion polymerization exhibited good absorption of the monomer phase. The pore size distribution of the beads was evaluated by mercury instrusion method. The surface area was calculated from the BET isotherms of nitrogen adsorption and desorption. The beads were modified to be a normal-phase liquid chromatographic (NPLC) stationary phase for high performance liquid chromatography (HPLC) in the following steps. First, the beads were completely hydrolyzed. Second, hydrolyzed particles were reacted with epichlorihydrin followed by another hydrolysis of the newly introduced epoxide groups. The retention properties of the NPLC stationary phase were easily modulated by changes in the composition of the mobile phase. The performance of theses beads was demonstrated with the separation of a variety of polar compounds. The satisfactory results were obtained.

Preparation of High-capacity, Monodisperse Polymeric Weak Cation Exchange Packings Using Surface-initiated Atom Transfer Radical Polymerization and Its Chromatographic Properties

“…13 2.0 g of 1.7 µm dispersed linear poly-styrene seed beads with low molecular weight (＜10 4 ) were prepared by dispersion polymerization, 14 and 60 mL of 5% PVA (w/w) of aqueous solution were placed in a 500 mL flask at room temperature, slowly stirred using a mechanical stirrer. 25.0 g of the mixture consisting of 3.8 mL CMS, 3.8 mL DVB, 8.7 mL toluene, 8.7 mL dibutyl phthalate, and 2% (w/w) (based on the total monomers) of BPO initiator were added into 250 mL aqueous solution of 0.2% (w/w) SDS and 5% (w/w) PVA, and then emulsified under ultrasonic condition until the size of oil drops became, at most, 0.5 µm (observed by optical microscope).…”

Preparation and modification of PS–PMMA microspheres and their application in high performance liquid chromatography

“…Currently, polymeric microspheres are mainly used in high performance liquid chromatography (HPLC) as a stationary phase, and their surface is modified with certain functional groups to provide them with certain properties. The common substrates of polymer microspheres are polystyrene (PS), 1 polymethyl methacrylate (PMMA), 2 and poly(glycidyl methacrylate) (PGMA), 3,4 which are widely used in HPLC columns due to their reactivity, low cost, acid and base resistance, and biocompatibility. 5…”