Self-assembled polyaniline (PANI) nanotubes were prepared in the presence of three different polymeric acids as dopants, namely poly(4-styrenesulfonic acid) (PSSA), poly(acrylic acid) (PAA) and poly(methyl vinyl ether-alt-maleic acid) (PMVEA) by oxidative polymerization using ammonium persulfate as the oxidant. The molecular structure of polymeric acids had a significant effect on the morphology and size of the polyaniline nanotubes as determined by SEM. The PANI nanotubes were also characterized by FTIR spectroscopy and electron paramagnetic resonance spectroscopy. (c) 2007 Elsevier B.V. All rights reserved.