A strong inorganic acid‐initiated methacrylate polymerization strategy for room temperature preparation of monolithic columns for capillary electrochromatography

Abstract

A facile strong inorganic acid-initiated methacrylate polymerization strategy was developed for fabricating monolithic columns at room temperature. The prepared monoliths were characterized by FTIR spectrometry, mercury intrusion porosimeter and SEM, while their performance was evaluated by CEC for the separation of various types of compounds including alkyl benzenes, polycyclic aromatic hydrocarbons, nonsteroidal anti-inflammatory drugs, anilines, and nitrophenol isomers. The column-to-column and batch-to-batch reproducibility for the prepared monoliths in terms of the RSD of EOF flow velocity, retention factor, and the minimum plate height of naphthalene ranged from 3.4 to 12.4%. The fabricated monoliths gave excellent performance for the separation of the test neutral compounds with the theoretical plates of 170 000-232 000 plates per meter for thiourea, and 77 400-112 300 plates per meter for naphthalene. The proposed strong inorganic acid-initiated methacrylate polymerization strategy is a promising alternative for fabricating organic polymer-based monoliths.

Investigation of neutral monolithic capillary columns with varying n‐alkyl chain lengths in capillary electrochromatography

“…In their work, a ternary porogenic solvent made of cyclohexanol, EG, and water in the ratio 75.7:20.7:3.6 wt% proved to be the optimal porogen to obtain an ODM monolith with reasonable EOF and high separation efficiency. Initially, in the present investigation, the C16‐monolith was prepared by free radical polymerization using two different initiators, AIBN (1.0 wt% with respect to monomers) and nitric acid [] (0.06 mmol), and a ternary porogenic solvent introduced by Karenga and El Rassi [] and made of cyclohexanol, EG, and water in the ratio 75.7:20.7:3.6 wt% for the former initiator and in the ratio 82.5:14.9:2.5 wt% for the latter initiator. Using 30:70 wt% of monomers (functional monomer and PETA crosslinker) to porogen, the latter monolithic column with the nitric acid initiator provided high separation efficiency of 145 000 plates/m for benzene and ABs (see Fig.…”

Nanoparticle-based monoliths for chromatographic separations

“…As one of the important members in the eld of carbonaceous NPs, graphene oxide (GO) has attracted signicant interest because of its unique properties and potential diverse applications, and thus novel stationary phases based on GO for chromatography are expected. Wang's group 63 reported the fabrication of GO-incorporated monolithic column via a roomtemperature strong inorganic acid-initiated methacrylate polymerization strategy 64 for CEC application. GO not only possesses the stability and large surface area that are necessary for separation media, it could also modify EOF in CEC and provide hydrophobicity and p-p electrostatic stacking properties.…”

Development and Pharmaceutical Applications of Functional Stationary Phases for Capillary Electrochromatography and Chiral Separation

“…A weakly ionic monomer is an alternative; but the use of it is limited [30,31] because it is a weak EOF generator. Therefore, compared to AMPS, high content of MAA was employed in order to increase the ionizable functional groups (i.e.…”