title: Separation and determination of degradation products of acid orange 7 by capillary electrophoresis/capacitively coupled contactless conductivity detector.
abstract: Capillary electrophoresis (CE) with capacitively coupled contactless conductivity detector (C(4)D) was developed to separate azo-dyestuff acid orange 7 (AO7) and its six degradation products. The analyzed products were sulfamic acid, oxalic acid, benzenesulfonic acid, 4-hydroxybenzene sulfonic acid, phthalic acid, and 4-aminobenzene sulfonic acid. In developing the method, types and concentrations of running buffers, injecting voltage and time, and applied voltage were tested to obtain optimum conditions to analyze target compounds. The separation was successfully achieved within 10 min using a fused-silica capillary under the following conditions: 20 mmol L(-1) acetate acid buffer, electrokinetic injection of -12 kV × 10 s, and applied voltage of -13 kV. The developed method was applied to analyze degradation products in situ during the reaction of AO7 with Fenton reagent (Fe(II)+H2O2 at pH 4.0).
authors.affiliation: School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.forename: Ya
authors.initials: Y
authors.lastname: Xiong
authors.forename: Tianyao
authors.initials: T
authors.lastname: Xie
authors.forename: Virender K
authors.initials: VK
authors.lastname: Sharma
authors.forename: Yuting
authors.initials: Y
authors.lastname: Tu
authors.forename: Jiannan
authors.initials: J
authors.lastname: Yang
authors.forename: Shuanghong
authors.initials: S
authors.lastname: Tian
authors.forename: Chun
authors.initials: C
authors.lastname: He
mesh_terms: D001391:Azo Compounds / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification*; D001557:Benzenesulfonates / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification*; D004553:Electric Conductivity; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D006861:Hydrogen Peroxide / Q000737:chemistry; D007501:Iron / Q000737:chemistry; D015394:Molecular Structure; D019815:Oxalic Acid / Q000032:analysis; D010795:Phthalic Acids / Q000032:analysis; D015203:Reproducibility of Results; D013451:Sulfonic Acids / Q000032:analysis; D013997:Time Factors
chemical_list: D001391:Azo Compounds; D001557:Benzenesulfonates; C045076:Fenton's reagent; D010795:Phthalic Acids; D013451:Sulfonic Acids; C032365:benzenesulfonic acid; C032279:phthalic acid; D019815:Oxalic Acid; C005741:sulfamic acid; D006861:Hydrogen Peroxide; D007501:Iron; C014722:2-naphthol orange