title: Anion exchange silica monolith for capillary liquid chromatography.
abstract: An anion exchange monolithic silica capillary column was prepared by surface modification of a hybrid monolithic silica capillary column prepared from a mixture of tetramethoxysilane (TMOS) and methyltrimethoxysilane (MTMS). The surface modification was carried out by on-column copolymerization of N-[3-(dimethylamino)propyl]acrylamide methyl chloride-quaternary salt (DMAPAA-Q) with 3-methacryloxypropyl moieties bonded as an anchor to the silica surface to form a strong anion exchange stationary phase. The columns were examined for their performance in liquid chromatography (LC) and capillary electrochromatography (CEC) separations of common anions. The ions were separated using 50 mM phosphate buffer at pH 6.6. Evaluation by LC produced an average of 30,000 theoretical plates (33 cm column length) for the inorganic anions and nucleotides. Evaluation by CEC, using the same buffer, produced enhanced chromatographic performance of up to ca. 90,000 theoretical plates and a theoretical plate height of ca. 4 mum. Although reduced efficiency was observed for inorganic anions that were retained a long time, the results of this study highlight the potential utility of the DMAPAA-Q stationary phase for anion separations.
authors.affiliation: Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM, Skudai, Malaysia. jafariah@kimia.fs.utm.my
authors.forename: Jafariah
authors.initials: J
authors.lastname: Jaafar
authors.forename: Yuta
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Tohru
authors.initials: T
authors.lastname: Ikegami
authors.forename: Kosuke
authors.initials: K
authors.lastname: Miyamoto
authors.forename: Nobuo
authors.initials: N
authors.lastname: Tanaka
mesh_terms: D000178:Acrylamides / Q000737:chemistry; D000838:Anions / Q000737:chemistry / Q000302:isolation & purification; D001959:Bromates / Q000302:isolation & purification; D002850:Chromatography, Gel / Q000379:methods*; D007452:Iodates / Q000302:isolation & purification; D007454:Iodides / Q000302:isolation & purification; D008737:Methyl Chloride / Q000031:analogs & derivatives; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D013861:Thiocyanates / Q000302:isolation & purification; D013890:Thiourea / Q000302:isolation & purification
chemical_list: D000178:Acrylamides; D000838:Anions; D001959:Bromates; D007452:Iodates; D007454:Iodides; D012821:Silanes; D013861:Thiocyanates; C071718:methyltrimethoxysilane; C061205:tetramethoxysilane; D012822:Silicon Dioxide; D008737:Methyl Chloride; D013890:Thiourea; C031760:thiocyanate