Poly(ethylene glycol) diacrylate based monolithic capillary columns for the analysis of polar small solutes by capillary electrochromatography

Abstract

Monolithic stationary phases based on poly(ethylene glycol) diacrylates for capillary electrochromatography were developed. Several poly(ethylene glycol) diacrylates (M 250, 575, and 700) were used as single monomers and the resulting columns were carefully compared. Methanol and ethyl ether were selected as porogenic solvents, and in all cases ultraviolet radiation was selected as initiation method to prepare polymeric monoliths. The influence of the monomer chain length and ratio monomer/porogen on the morphological and electrochromatographic properties of the resulting monoliths was investigated. Several families of compounds with different polarity (alkyl benzenes, organophosphorous pesticides, benzoic acid derivatives, and sulfonamides) were selected to evaluate the performance of the fabricated monolithic columns. The best results were obtained for poly(ethylene glycol) diacrylate 700 monoliths affording efficiencies of 144 000 plates/m for retained polar aromatic small molecules and excellent reproducibility in column preparation (RSD values below 2.5%).

Recent developments of monolithic and open‐tubular capillary electrochromatography (2017–2019)

“…The most commonly used preparation method of polymer stationary phase with the desired surface chemistry was carried out via a one‐step molding process of direct in situ copolymerization of the functional monomer, crosslinker, initiator, and in the presence of an appropriate porogen . Concentration and composition of organic monomers are the main factors that affect the characters of monolithic column .…”

“…Although hydrophilic monolithic columns have been widely reported on the separation of polypeptides and other substances , the separation of acidic substances remains a challenge. The migration direction of acidic analytes and monolithic columns’ EOF is opposite, which may prolong the analysis time or even unable to be eluted out.…”

Advances in capillary electro-chromatography

“…Vergara-Barberán et al. [54] synthesized a series of monolithic columns using poly(ethylene glycol) diacrylates (PEGDA, Mn 250, 575 and 700) as single monomers in a binary porogen solvent of methanol and ethyl ether. By comparing the chromatographic performance of these columns, the PEGDA 700 monolithic column exhibited the best separation performance for alkylbenzenes, organophosphorous pesticides (OPPs), benzoic acid derivatives and sulfonamides (Fig.…”

“…The separations of small organic molecules consisting of alkylbenzenes [12,13,25,27,28,32,48,50,52,54,58,64,66], PAHs [18,28,37,43,48,52,[63], [64], [65]], chlorobenzenes [13,14,32,50], aromatic acids [13,39,49,53,54], phenols [14,15,17,18,48,50,52,53,58,59,62,68], anilines [12,25,28,39,48,52,62,64], parabens [29] and organophosphorus pesticides [54] have been investigated, while the separations of drugs such as cephalosporin antibiotics [20,29], impurities of pramipexole [57], sulfonamides [29,32,54] and non-steroidal anti-inflammatory drugs [27,32,63], especially the plant natural ingredients including purine alkaloids [55], flavonoids [16] and phenoxyacids [14,56], have been achieved. Biological molecules, amino acids [27,32,50], peptides [32,35,44,53], nucleotides [57], nucleosides [32,44,57], nucleobases [44,59], monoamine neurotransmitters [16] and proteins [[36], [37],…”

Recent advances in the bioanalytical methods of polyethylene glycols and PEGylated pharmaceuticals

“…Polyethylene glycol (PEG) is one of the most important synthetic hydrophilic polymers in chemical and pharmaceutical industry, which can be linear or branched and consists of oxyethylene repeating units of 44 Da in mass [1–4]. Generally PEGs are nontoxic, non‐immunogenic, and non‐antigenic and therefore have been approved for intravenous, oral, and dermal administrations for human use by the authorities of most countries/areas [5–9].…”