Synthesis of ionic liquid‐bonded organic‐silica hybrid monolithic column for capillary electrochromatography

Abstract

An ionic liquid (IL) was introduced into the organic-silica hybrid monolithic column as the stationary phase for capillary electrochromatography (CEC). The monolithic silica matrix containing chloropropyl functional group was prepared by the in situ co-condensation of tetramethoxysilane and (3-chloropropyl)-trimethoxysilane via a sol-gel process and chemical modification with N-methylimidazole. The electroosmotic flow of the IL-modified hybrid monolithic column was reversed at acidic pH and the morphology of the column was characterized by scanning electron microscope. Four aromatic hydrocarbons were completely separated with 40% acetonitrile phosphate buffer as the mobile phase and seven inorganic ions were efficiently separated with the phosphate buffer on the column in CEC. Reproducibilities of migration time for four aromatic hydrocarbons (benzene, naphthalene, anthracene, chrysene) were acceptable on IL-modified hybrid monolithic columns. Relative standard deviations of run-to-run (n=5), peak area-to-peak area (n=5), day-to-day (n=3) and column-to-column (n=3) were in the range of 0.72-0.88, 1.47-5.40, 2.44-4.99 and 3.01-8.11%, respectively.

Combined use of cyclofructans and an amino acid ester‐based ionic liquid for the enantioseparation of huperzine A and coumarin derivatives in CE

“…ILs are organic salts with melting points at or below 100°C. Due to their unique properties (good thermal stability, negligible vapor pressure, tunable viscosity, and miscibility with water and organic solvents), ILs have been widely used in different scientific areas, such as organic synthesis, catalysis, extraction, and separation science . Recently, a new class of CILs, derived from amino acids (amino acid ester based ILs, AAILs), was synthesized and used, for the first time, in CE.…”

Monolithic column functionalized with quinine derivative for anion‐exchange capillary electrochromatography

“…Meanwhile, the organic polymer monolithic column with anion‐exchange interaction exhibits good performance and gets more and more attention. Acrylamides and ionic liquids are often used as functional monomers to form anion‐exchange stationary phases. With the development of this kind of monolithic columns, the monomers are increasingly scarce.…”

Application of dispersive liquid-liquid microextraction with 3-metyl-1-octyl imidazolium tetrafluoroborate as an extractant for the electrophoretic determination of steroid hormones in urine sample

“…1. The general scheme of dispersive liquid-liquid microextraction [7] костям (ИЖ) [10][11][12][13][14], нашедшим применение в различных вариантах микроэкстракции: экстракция в каплю [15][16][17], гомогенная жидкостно-жидкостная микроэкстракция (Homogeneous Liquid-Liquid Microextraction, HLLME) [18,19], в которой в качестве экстрагентов могут применяться и гидрофильные ионные жидкости. В [20] Реактивы.…”