Grafting of Tetraphenylethylene on Silica Surface, Characterizations, and Their Chromatographic Performance as Reversed-Phase Stationary Phases

Abstract

Surface modification is an effective way to functionalize the materials so as to get some special properties. Tetraphenylethylene (TPE) has been widely investigated as a well-known reagent which has the nature of aggregation-induced emission (AIE), but has never been reported in the liquid chromatography stationary phase. In this work, TPE-grafted silica (Sil-TPE) was obtained successfully using the derivative of 1-(4-hydroxyphenyl)-1,2,2-triphenylethylene as a ligand, and then characterized by elemental analysis, Fourier transform infrared spectra, thermogravimetric analysis, and so forth. Laser scanning confocal microscopy images reflected the AIE phenomenon of grafted TPE because the internal vibration and rotation of TPE molecules were restrained in the confined silica space. The contact angle test showed superhydrophobic properties of Sil-TPE. In order to understand thoroughly the mechanism of chromatographic performance and retention behavior for Sil-TPE, Tanaka test mixture, alkylbenzenes, polycyclic aromatic hydrocarbons (PAHs), and phenols were separated. This reveals that Sil-TPE has strong aromaticity and certain shape selectivity, especially, has excellent separation performance for PAHs and phenols. The thermodynamic properties and repeatability of Sil-TPE were further studied, which showed the stability of Sil-TPE. This work shows that TPE can be successfully grafted on silica surface and it has the potential to be a new kind of promising stationary phases in the future.

Design of β-Alanine-Derived Novel C18 Stationary Phase Containing Embedded Urea and Amide Groups for the Separation of Versatile Analytes

“…Moreover, Tanaka tests for the HILIC mode separation was also used to characterize the phase to observe the applicability for the diverse analytes. First, the Tanaka test was carried out to compare parameters such as hydrophobicity, steric hindrance or shape selectivity, silanol capacity, and ion exchange capacities at high and low pH, and results are presented in Table S6 (Supporting Information) . These tests were designed to assess selectivity and retention properties among different RP columns, not column efficiency.…”

“…First, the Tanaka test was carried out to compare parameters such as hydrophobicity, steric hindrance or shape selectivity, silanol capacity, and ion exchange capacities at high and low pH, and results are presented in Table S6 (Supporting Information). 57 These tests were designed to assess selectivity and retention properties among different RP columns, not column efficiency. Therefore, the selectivity and retention behavior of the new phase has been considered and compared to the commonly used commercial columns (C18 (Reprosphere C18-NE), C30 (RP AQUE-OUS), and amide-bonded C18 (Ascentis RP-Amide)).…”

A C4-modified bipyridinium multi-mode stationary phase for reversed phase, hydrophilic interaction and ion exchange chromatography

“…Nowadays, the stationary phases based on a single retention mechanism are well developed and applied. RPLC can be used to effectively separate organic compounds, [6][7][8][9][10] HILIC is mainly used for the separation of polar analytes, [11][12][13] and IEC is usually used for separating ionic compounds by ion exchange mechanism. 14 However, with the development of analytical chemistry in the elds of the environment, pharmacometabonomics, food and biotechnology, chromatographic stationary phases with a single retention mechanism cannot enable the separation and analysis of highly mixed analytes comprising polar, non-polar and ionic compounds.…”

Non-porous silica support covalent organic frameworks as stationary phases for liquid chromatography

“…The Δ G < 0 for the analyte indicates that the separation of the analyte in the NPS@TPB-DMTP column is a thermodynamically spontaneous process. 8,16,28–30…”

“…The DG o 0 for the analyte indicates that the separation of the analyte in the NPS@TPB-DMTP column is a thermodynamically spontaneous process. 8,16,[28][29][30] Monosubstituted benzenes were injected 10 times in succession to assess the reproducibility of the NPS@TPB-DMTP column. After 10 injections, the chromatograms were almost unchanged (Fig.…”