title: Simultaneous voltammetric determination for DA, AA and NO₂⁻ based on graphene/poly-cyclodextrin/MWCNTs nanocomposite platform.
abstract: In the present work, graphene sheets (GS) and multiwall carbon nanotubes (MWCNTs) were dispersed in the mixed solution of cyclodextrin (CD) and cyclodextrin prepolymer (pre-CD) and were used as modifier to fabricate chemical modified electrode to simultaneous detect dopamine (DA), ascorbic acid (AA) and nitrite (NO2(-)). CD cross-linked pre-CD (CDP) displays excellent film forming ability, which made the electrode stable. Comparing with CDP-GS, CDP-MWCNTs and CDP-GS-MWCNTs modified electrodes, the CDP-GS-MWCNTs displays higher catalytic activity and selectivity toward the oxidation of DA, AA and NO2(-), revealing that MWCNTs effectively inhibited the stacking of individual GS and enhanced the utilization of GS based composites. The host-guest chemical reaction ability of CD and π-π stacking interaction between detected molecules and GS-MWCNTs surface were considered as the main reasons of the successfully simultaneous detection of DA, AA and NO2(-). Cyclic voltammetry (CV), scanning electron microscopy (SEM) and different pulse voltammetry (DPV) were employed to characterize the biosensor. The linear response range for AA, DA and NO2(-) were 5 μM-0.48 mM, 0.15-21.65 μM and 5 μM-6.75 mM, respectively and the detection limits were 1.65 μM, 0.05 μM and 1.65 μM.
authors.affiliation: Key Laboratory of Analytical Chemistry (Chongqing), College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Chai
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Li
authors.forename: Xia
authors.initials: X
authors.lastname: Zhong
authors.forename: Huaan
authors.initials: H
authors.lastname: Zhong
mesh_terms: D001205:Ascorbic Acid / Q000737:chemistry / Q000302:isolation & purification*; D015374:Biosensing Techniques; D004298:Dopamine / Q000737:chemistry / Q000302:isolation & purification*; D004563:Electrochemistry; D006108:Graphite / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry; D009573:Nitrites / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D037742:Nanotubes, Carbon; D009573:Nitrites; D006108:Graphite; D001205:Ascorbic Acid; D004298:Dopamine