Acid yellow 9 as a dispersing agent for carbon nanotubes: preparation of redox polymer-carbon nanotube composite film and its sensing application towards ascorbic acid and dopamine.
In this study, we show that acid yellow 9 (4-amino-1-1'-azobenzene-3,4'-disulfonicacid, AY) is a good stabilizing agent for multi-walled carbon nanotubes (MWCNTs). MWCNTs dispersed in AY solution was remained stable about three months and even remained stable after centrifugation at 10,000 rpm for 30 min. Using MWCNTs/AY dispersion, thin-films were prepared on indium tin oxide coated glass electrode and glassy carbon electrodes. Further, dried films of MWCNTs/AY were subjected to electropolymerization in 0.1M H(2)SO(4) solution. Adsorbed AY molecules on MWCNTs get polymerized and they yield a polymer-MWCNTs nanocomposite film on electrode surface which is found to be electrochemically active in wide pH range (1-11). Characterization studies were performed using cyclic voltammetry and SEM. These studies are supported that hybrid material PAY/MWCNTs was obtained. Moreover, newly synthesized PAY-MWCNTs composite film showed excellent electrocatalytic activity towards oxidation of dopamine (DA) and ascorbic acid (AA) with high sensitivity in physiological pH. Linear sweep voltammetry was employed to the determination of DA in the presence of AA in the range of 2x10(-7) to 1.4x10(-6) M. Amperometry was employed to determination of AA at 0.0 V in the range from 1x10(-6) to 5.6x10(-5) M, and DA, uric acid are not interfered on the steady-state current of AA. In addition, real samples such as dopamine injection and AA spiked into human urine were analyzed using PAY/MWCNTs composite modified electrode and satisfactory results were obtained.
Kumar
S Ashok
SA
Department of Materials and Mineral Resources Engineering, National Taipei University of Technology, Taipei, Taiwan. sakumar80@gmail.com
Wang
Sea-Fue
SF
Yang
Thomas C-K
TC
Yeh
Chun-Ting
CT
D001205:Ascorbic Acid / Q000032:analysis*; D001391:Azo Compounds; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D004298:Dopamine / Q000032:analysis*; D006801:Humans; D008855:Microscopy, Electron, Scanning; D037742:Nanotubes, Carbon / Q000648:ultrastructure; D010084:Oxidation-Reduction; D011108:Polymers
D001391:Azo Compounds; D037742:Nanotubes, Carbon; D011108:Polymers; D001205:Ascorbic Acid; D004298:Dopamine