氧化石墨烯修饰多孔复合涂层超长开管液相色谱柱的制备与评价

Preparation and Evaluation of Graphene Oxide Modified Porous Composite Layer Open Tubular Capillary Column for Capillary Liquid Chromatography

采用原位聚合法在毛细管柱（3 m×25μm i.d.）内壁制备粗糙结构的聚氯甲基苯乙烯二乙烯基苯涂层,并将氧化石墨烯以共价键合的方式固定在涂层表面,制备成氧化石墨烯修饰多孔复合涂层超长开管毛细管液相色谱柱。通过扫描电镜、透射电镜、拉曼光谱等手段对固定相的结构进行表征,证实聚氯甲基苯乙烯二乙烯基苯涂层具有球形分散结构,而片状的氧化石墨烯均匀覆盖在聚合物层表面。球状的聚合物层及氧化石墨烯的覆盖极大地提高了色谱柱的相比及样品容量,乙腈-水为流动相可分离烷基苯、中性多环芳烃、酸性和碱性化合物,乙腈-0.02 mol/L醋酸铵为流动相可实现4种核酸碱基样品的分离。制备的色谱柱具有良好的重复性和稳定性,测试的日内、日间、柱间重复性（n=6）相对标准偏差（RSD）均在0.3%~2.0%范围内。

Graphene oxide （GO） modified stationary phase for open tubular capillary （3 m ＆#215; 25 μm i. d. ） of liquid chromatography （ OT-CLC） was fabricated by coating GO sheets onto poly （ vinylbenzyl chloride-divinylbenzene） porous composite layer via covalent coupling, which was prepared by in-situ polymerization. Scanning electron microscopy （ SEM）, Raman spectroscopy and transmission electron microscopy （ TEM） were used to characterize the structure of the stationary phase. The results demonstrated that poly（vinylbenzyl chloride-divinylbenzene） porous composite layer had decentralized globular structure, and the GO sheets covered on the porous layer homogenously. The phase ratio and sample capacity were greatly improved due to the spherical polymer layer and the coverage of GO. Thus, alkyl benzenes, neutral polycyclic aromatic hydrocarbons, acidic and basic compounds could be well separated by using acetonitrile-water as eluent, while four nucleobases were completely separated by using acetonitrile-0. 02 mol/ L ammonium acetate as mobile phase. The run-to-run, day-to-day, and column-to-column reproducibilities were evaluated by calculating the relative standard deviations （RSDs, n =6） of the retention time of o-phenylenediamine, aniline and 2, 4, 6-trifluoroaniline, respectively. These RSD values were all in the range of 0. 3% -2. 0% .