title: Mussel-inspired polydopamine-assisted hydroxyapatite as the stationary phase for capillary electrochromatography.
abstract: A novel capillary with hydroxyapatite (HAP) as the stationary phase was prepared for open-tubular capillary electrochromatography (OT-CEC). To immobilize HAP, a mussel-inspired polydopamine method was utilized to modify the capillary firstly, generating a polydopamine layer; and then a layer of HAP would be formed on the polydopamine layer by a biomineralization process, to produce a HAP-modified capillary (HAP@capillary). Scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS) and X-ray photoelectron spectroscopy (XPS) provided evidence of nanostructured HAP grown on the surface of the capillary wall. The electroosmotic flow (EOF) characteristic of the HAP@capillary was investigated by varying the percentage of acetonitrile and pH value of the buffer with thiourea as a marker, and a pH-dependent EOF from anode to cathode was observed. The HAP@capillary exhibits high column efficiency for methylbenzene, up to 151,138 plates per meter. Different kinds of compounds including alkylbenzenes, phenols and amines have been successfully separated by the HAP@capillary in CEC mode. The HAP@capillary also possessed good separation ability in capillary liquid chromatography (CLC) mode because of the relatively large ratio of HAP in the capillary; however, the separation efficiency was not as good as that in CEC mode. The reproducibilities of the HAP@capillary were evaluated, and the relative standard deviations were found to be lower than 5%.
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan, 430071, China. chenzl@whu.edu.cn.
authors.forename: Juan
authors.initials: J
authors.lastname: Zhang
authors.forename: Wenpeng
authors.initials: W
authors.lastname: Zhang
authors.forename: Tao
authors.initials: T
authors.lastname: Bao
authors.forename: Zilin
authors.initials: Z
authors.lastname: Chen
mesh_terms: D000818:Animals; D049872:Bivalvia; D053801:Capillary Electrochromatography / Q000379:methods*; D017886:Durapatite / Q000737:chemistry* / Q000302:isolation & purification; D007211:Indoles / Q000737:chemistry* / Q000302:isolation & purification; D011108:Polymers / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D007211:Indoles; D011108:Polymers; C568283:polydopamine; D017886:Durapatite