Formation and properties of a novel complex composed of an amylose-grafted chitosan derivative and single-walled carbon nanotubes

The water-soluble chitosan derivative grafted with short amylose chains (Chit-Amy-Ill) was synthesized through the phosphorylase-catalyzed enzymatic polymerization, following that the chitosan was grafted with maltoheptaose residues by reductive amination. The chemical structures were characterized by FTIR, H-1 NMR, Raman, XRD and static light scattering analyses. The results indicated that the amylose chains were conjugated with the chitosan backbone through the reductive Shiff base bonds (-CH-NH-), and the polymerization degree of the grafted amylose chains was about 25. The dispersion stability of single-walled carbon nanotubes (SWNTs) in water was improved through the complexation of Chit-Amy-III derivatives with SWNTs. Raman, XRD and TEM analyses confirmed that the resultant Chit-Amy-SWNTs complex was formed by the wrapping of the Chit-Amy-III derivative around the SWNTs. The results of electrochemical analysis indicated that the Chit-Amy-SWNTs complex modified electrode displayed excellent electron conductivity and electrocatalytic activity on H2O2. (C) 2011 Elsevier Ltd. All rights reserved.