Fig. 1B shows the CVs of the same compounds at the surface of the SWCNT/CCE. The CV of APAP on the surface of the SWCNT/CCE shows a pair of well-defined redox transitions with anodic and cathodic peak potentials at 390 and 330 mV, respectively (curve 2). On the other hand, the anodic peak potential of APAP shifts from 420 mV at the bare CCE to 390 mV at the SWCNT/CCE, and the anodic peak current is enhanced by approximately 4-fold in comparison with the anodic peak current on CCE. However, the anodic peak potential for the oxidation of AA occurs at 70 mV, which is approximately 245 mV more negative than that at the bare CCE, and the anodic peak current is enhanced by approximately 3-fold in comparison with the anodic peak current on the CCE. The decrease of oxidation overpotential, accompanied by a significant increase in the oxidation current of AA and a pair of symmetric redox peaks with greatly enhanced peak current and smaller peak separation for APAP, strongly indicates excellent catalytic ability of SWCNTs on the oxidation of these compounds. These observations demonstrate that SWCNTs accelerate the oxidation of AA and APAP.