Fast preparation of polystyrene-based monolith using microwave irradiation for micro-column separation

Abstract

The conventional analytical HPLC was successfully developed for micro-column separation by using a simple eluate splitting system, a self-preparation of monolithic column and an on-capillary column detector in our laboratory. A typical polystyrene-based monolith was quickly prepared inside the fused-silica capillary, which in situ polymerization was carried out in 10 min by microwave irradiation. The reactant solution consisted of styrene (ST) as a functional monomer, divinylbenzene (DVB) as a cross-linking agent, toluene and isooctane as porogenic solvents, and azobisisobutyronitrile (AIBN) as an initiator. The monolith was proved to form in the center of the capillary and adhered to the column inner wall by the scanning electron micrograph. Its chromatographic behaviors were evaluated in detail by varying the flow rate and percentage of mobile phases, and under the optimal condition, baseline separation of the model analytes including thiourea, benzene, toluene, ethylbenzene was obtained with a highest theoretical plate number near 11,290 N/m by the developed capillary HPLC. Furthermore, the stability and porosity of the prepared monolith were systematically investigated by a simple flow method.

Preparasi Kolom Microbore Monolith Berbasis Polistirena untuk Pemisahan Alkilbenzena Menggunakan Kromatografi Cair Kinerja Tinggi

“…Dari hasil percobaan ini dapat diketahui bahwa monolith III merupakan monolith dengan komposisi terbaik untuk dapat diaplikasikan dalam pemisahan molekul alkilbenzena berukuran kecil, dengan nilai N mencapai 17260 plate/m kolom. Nilai N pada monolith ini lebih besar daripada monolith serupa yang dikembangkan oleh Zhang et al [8] …”

“…Penggunaan porositas dan ukuran pori yang dapat divariasi, monolith terbukti dapat berfungsi sebagai media pemisahan dalam kromatografi untuk pemisahan berbagai analit, mulai dari molekul berukuran kecil [3,[7][8], hingga makromolekul seperti peptida dan protein [9][10], dan juga oligodeoxythymidylic acids [2].…”

Preparation and evaluation of poly(alkyl methacrylate-co-methacrylic acid-co-ethylene dimethacrylate) monolithic columns for separating polar small molecules by capillary liquid chromatography

“…The higher amount of hydrophilic monomer HEMA in the monomer composition reduced hydrodynamic permeability of the resulting monolithic stationary phases and improved column efficiency in separating small molecules. Another approach, addition of methacrylic acid (MAA) into either the polystyrene-based monoliths for reversed-phase capillary LC analysis or the EDMA-based monoliths for hydrophilic interaction chromatography (HILIC), was also performed by various research groups in order to increase hydrophilic interactions between analytes and monolithic stationary phases [31][32][33][34]. By adding MAA, Svobodová et al [32] successfully synthesized a poly(styrene-DVB-MAA) monolithic column (320-mm i.d., 17-cm long) for capillary LC analysis of small molecules.…”

Synthesis of divinylbenzene polymer/Fe 3 O 4 hybrid monolithic column for enrichment and online thermal desorption of methylmercury in real samples

“…Compared with inorganic silica-based adsorbents, polymeric materials have some intrinsic advantages. For example, their use with liquids within the entire range of pH is possible [21,22]. In this paper, a divinylbenzene polymer (DVB)/Fe 3 O 4 hybrid monolithic column was prepared for the preconcentration of MeHg in sample solution, which had not been indicated in other publications.…”