EFFECT OF SINGLE-WALLED CARBON NANOTUBES ON HYDROXYPROPYL-β-CYCLODEXTRIN STATIONARY PHASE

Abstract

In the present work, we describe a novel application of functionalized single-walled carbon nanotubes (SWCNTs) as a stationary phase for the liquid chromatographic separation of polycyclic aromatic hydrocarbons and structurally similar analogues. The SWCNTs were first oxidized to give carboxylic derivatives (SWCNT-COOH), afterwards these were covalently derivatized with hydroxypropyl-β-cyclodextrin (HP-β-CD). Then, the HP-β-CD-SWCNTs were bonded to silica gel with 3-(triethoxysilyl) propyl isocyanate, which were used as a stationary phase to separate the investigated solutes by HPLC. On this stationary phase, eight polycyclic aromatic hydrocarbons were separated using water/methanol (5:5, v/v) as the mobile phase and six structurally similar dipine drugs were also separated using (3:7, v/v) methanol/triethylammonium acetate buffer (0.1%, v/v, pH 4.1) as the mobile phase. The results showed that the HP-β-CD-SWCNTs stationary phase had stronger separation ability for the aromatic hydrocarbons and analogues compared with the HP-β-CD stationary phase. This method can be used to improve the separation efficiency of the β-CD stationary phases, and the HP-β-CD-SWCNTs column can be used for the determination of the aromatic hydrocarbons in wastewater.

Multi-walled carbon nanotubes: innovative sorbents for pre-concentration of polychlorinated biphenyls in aqueous environments

“…2 Surface-modied CNTs have therefore been used in biosensors, 8 electrochemical sensors, 9 diagnostics imaging, 10,11 drugdelivery systems, 12 nanocomposites, 13 and in general separation sciences. 14 Furthermore, CNTs have been proposed as new generation of adsorbents in solid-phase extraction (SPE), facilitating the analysis of environmental pollutants. 15 Particularly, CNTs have been applied as adsorbents in SPE for quantication of polycyclic aromatic compounds, 16 phthalate esters, 17 polyhalogenated compounds, 18 and tetracyclines.…”

An innovative approach for separation and purification of natural products using carbon nanotube–alginate gel beads as a novel stationary phase

“…CNTs can be used to separate different classes of compounds aer surface modication. CNTs have been used as stationary phase in gas chromatography (GC) 8,9 and high performance liquid chromatography (HPLC) 10,11 for separation and determination of various types of material, such as esters and aromatics, 12,13 aliphatic alcohols, 14 and gas. 15 But CNTs as a new packing material in purication and separation of natural products has not been reported yet.…”

“…The surface of MWCNTs is more active, and usually reacts with a large number of surface groups, such as carboxyl and oxygen. 17 To investigate the adsorption and desorption properties of different CNTs towards natural products, two typical compounds were selected from each kind of acidic, alkaline, and neutral natural products, respectively. Then the most effective CNT was chosen to separate suitable natural products.…”