Click N-benzyl iminodiacetic acid: Novel silica-based tridentate zwitterionic stationary phase for hydrophilic interaction liquid chromatography

A novel approach that involved the grafting of diblock copolymer with two types of monomer onto substrate by sequential surface initiated-atom transfer radical polymerization was proposed to prepare a mixed-mode chromatographic stationary phase. The distinguishing feature of this method is that it can be applied in the preparation of various mixed-mode stationary phases. In this study, a new reverse-phase/ion-exchange stationary phase was prepared by grafting hydrophobic styrene and cationic sodium 4-styrenesulfonate by the proposed approach onto silica surface. The chromatographic properties of the prepared stationary phase were evaluated by the separation of benzene derivatives, anilines, and β-agonists, and by the effect of pH values and acetonitrile content on the retention. Compared with typical RP columns, the prepared stationary phase achieved the better resolution and higher selectivity at a shorter separation time and lower organic content. Moreover, the application of the prepared column was proved by separating widely distributed polar and charged compounds simultaneously.

Section: Resultsmentioning

confidence: 73%

Preparation and evaluation of diblock copolymer‐grafted silica by sequential surface initiated‐atom transfer radical polymerization for reverse‐phase/ion‐exchange mixed‐mode chromatography

Wang

Wei

2017

“…Meanwhile, compared with commercial HILIC (HILIC Atlantics) and ZIC HILIC (tradition lysine SP, TLSP) columns, CLSP afforded better retention and higher efficiency. The same research group also prepared a novel tridentate zwitterionic HILIC SP by CuAAC covalently bonding N ‐benzel iminodiacetic acid (IDA) on silica . IDA is a dicarboxylic acid amine, which can act as a tridentate ligand and produce stronger interaction with polar or charged compounds.…”

Section: Development Of New Hilic Stationary Phasesmentioning

confidence: 99%

Recent applications of hydrophilic interaction liquid chromatography in pharmaceutical analysis

Zhang

et al. 2016

Hydrophilic interaction liquid chromatography, an alternative liquid chromatography mode, is of particular interest in separating hydrophilic and polar ionic compounds. Compared with traditional liquid chromatography techniques, hydrophilic interaction liquid chromatography offers specific advantages mainly including: (1) relatively green and water-soluble mobile phase composition, which enhances the solubility of hydrophilic and polar ionic compounds; (2) no need for ion-pairing reagents and high content of organic solvent, which benefits mass spectrometry detection; (3) high orthogonality to reverse-phase liquid chromatography, well adapted to two-dimensional liquid chromatography for complicated samples. Therefore, hydrophilic interaction liquid chromatography has been rapidly developed in many areas over the past decades. This review summarizes the recent progress (from 2012 to July 2016) of hydrophilic interaction liquid chromatography in pharmaceutical analysis, with the focus on detecting chemical drugs in various matrices, charactering active compounds of natural products and assessing biotherapeutics through typical structure unit. Moreover, the retention mechanism and behavior of analytes in hydrophilic interaction liquid chromatography as well as some novel hydrophilic interaction liquid chromatography columns used for pharmaceutical analysis are also described.

“…Some zwitterionic stationary phases were obtained by separately bonding two kinds of selectors respectively containing positively and negatively charged groups in the structure . Amino acids and peptides are natural zwitterionic compounds and can be bonded on the surface of silica to prepare HILIC stationary phases . But the number of the amino and carboxyl groups may be different and the both groups can be in charged or neutral forms depending on the conditions of mobile phases, which would result in the stationary phase possessing partial charges and ion‐exchange/HILIC mixed‐mode retention.…”

Section: Introductionmentioning

confidence: 99%

Preparation and comparison of three zwitterionic stationary phases for hydrophilic interaction liquid chromatography

Qiao

Sun

2020

Surface‐bonded zwitterionic stationary phases have shown highlighted performances in separation of polar and hydrophilic compounds under hydrophilic interaction chromatography mode. So, it would be helpful to evaluate the characteristics of zwitterionic stationary phases with different arranged charged groups. The present work involved the preparation and comparison of three zwitterionic stationary phases. An imidazolium ionic liquid was designed and synthesized, and the cationic and anionic moieties respectively possessed positively charged imidazolium ring and negatively charged sulfonic groups. Then, the prepared ionic liquid, phosphorylcholine and an imidazolium‐based zwitterionic selector were bonded on the surface of silica to obtain three zwitterionic stationary phases. The selectivity properties were characterized and compared through the relative retention of selected solute pairs, and different kinds of hydrophilic solutes mixtures were used to evaluate the chromatographic performances. Moreover, the zwitterionic stationary phases were further characterized by the modified linear solvation energy relationship model to probe the multiple interactions. All the results indicated that the types and arrangement of charged groups in zwitterionic stationary phases mainly affect the retention and separation of ionic or ionizable compounds, and for interaction characteristics the contribution from n and π electrons and electrostatic interactions displayed certain differences.