title: Graphene quantum dots as additives in capillary electrophoresis for separation cinnamic acid and its derivatives.
abstract: A facile capillary electrophoresis (CE) method for the separation of cinnamic acid and its derivatives (3,4-dimethoxycinnamic acid, 4-methoxycinnamic acid, isoferulic acid, sinapic acid, cinnamic acid, ferulic acid, and trans-4-hydroxycinnamic acid) using graphene quantum dots (GQDs) as additives with direct ultraviolet (UV) detection is reported. GQDs were synthesized by chemical oxidization and further purified by a macroporous resin column to remove salts (Na2SO4 and NaNO3) and other impurities. Transmission electron microscopy (TEM) indicated that GQDs have a relatively uniform particle size (2.3 nm). Taking into account the structural features of GQDs, cinnamic acid and its derivatives were adopted as model compounds to investigate whether GQDs can be used to improve CE separations. The separation performance of GQDs used as additives in CE was studied through variations of pH, concentration of the background electrolyte (BGE), and contents of GQDs. The results indicated that excellent separation can be achieved in less than 18 min, which is mainly attributed to the interaction between the analytes and GQDs, especially isoferulic acid, sinapic acid, and cinnamic acid.
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People's Republic of China; University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
authors.forename: Yaming
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Key Laboratory of Bioelectrochemistry and Environmental Analysis of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730000, People's Republic of China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Bi
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People's Republic of China; University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People's Republic of China.
authors.forename: Litao
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People's Republic of China.
authors.forename: Xia
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People's Republic of China. Electronic address: sqdong@licp.cas.cn.
authors.forename: Shuqing
authors.initials: S
authors.lastname: Dong
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People's Republic of China. Electronic address: zhaol@licp.cas.cn.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhao
mesh_terms: D002934:Cinnamates / Q000032:analysis*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006108:Graphite / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D045663:Quantum Dots; D015203:Reproducibility of Results
chemical_list: D002934:Cinnamates; C029010:cinnamic acid; D006108:Graphite
keywords: Additives; Capillary electrophoresis; Cinnamic acid and its derivatives; Graphene quantum dots