Electrochemical analysis of ascorbic acid and uric acid on defect-engineered carbon nanotube networks with increased exposure of graphitic edge planes

In this work, defect-engineered carbon nanotube networks are grown in situ on a 316L stainless steel substrate using chemical vapor deposition and an annealing treatment. The defective carbon nanotube networks can be applied directly as electrodes for the simultaneous determination of ascorbic acid and uric acid using cyclic voltammetry and differential pulse voltammetry. Carbon nanotube networks annealed at 500 °C enable simultaneous determination of ascorbic acid and uric acid with linear responses from 100 to 3000 μM and from 10 to 150 μM, respectively. The excellent electrocatalytic activity of the defective carbon nanotube networks is attributed to the engineered defects and the large number of exposed edge planes.