Electrochemical Detection of Quinoline Yellow in Soft Drinks Based on Layer-by-layer Fabricated Multi-Walled Carbon Nanotube

摘要

A novel modified electrode based on multi-walled carbon nanotubes was fabricated by alternativelydepositing poly (diallyldimethylammonium chloride) functionalized MWCNT (PDDA-MWCNT) andpoly(sodium 4-styrenesulfonate) functionalized MWCNT (PSS-MWCNT) via a solution based layer- by-layer (LbL) self-assembly method followed by calcination, and applied for the electrochemicaldetection of quinoline yellow. The electrode modification process was monitored by UV-visspectroscopy which showed the linear growth of the film with the bilayer number. The electrocatalyticactivity of MWCNT modified electrode towards oxidation of quinoline yellow was evaluated usingcyclic voltammetry and amperometric method. Under the optimal conditions, the oxidation peakcurrent was proportional to quinoline yellow concentration in a wide range between 0.02 and 10 M,and the detection limit was 0.004 M (S/N = 3). In addition, the fabricated electrode also displayedexcellent reproducibility and stability, and employed to determinate quinoline yellow in soft drinks.