Polyaniline emeraldine base (EB) coated indium-tin oxide (ITO) electrode was prepared for the construction of a cell-based chip. Ultrathin polyaniline PANI film on an ITO was electroactive at neutral pH without co-deposition of an acidic counterion. HeLa cells were cultured on a PANI/ITO substrate and utilized to assess the biological toxicity of anticancer drugs. Cell growth, cell viability and drug-related cell toxicity were evaluated by a cyclic voltammetry (CV) method under a neutral pH. We demonstrated the functionality of a PANI coated ITO electrode for use as a cell chip and found that PANI was a good surface for the HeLa cells to grow without any significant morphological changes. (C) 2009 Elsevier B.V. All rights reserved.