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.