A novel electrochemical method to evaluate the cytotoxicity of heavy metals

A novel label-free electrochemical method based on the direct voltammetric response of human cervical carcinoma (HeLa) cells on a highly sensitive graphene modified electrode was developed. Five heavy metals were tested with this method. This work will be beneficial in providing a novel simple method for cytotoxicity evaluation of hazardous pollutants in environment. •The electrochemical behaviors of HeLa cells on a highly sensitive graphene modified electrode were proposed for the first time.•A novel label-free electrochemical method based on the electrochemical response of HeLa cells was developed.•Cytotoxicity of five heavy metals was tested with the electrochemical method. There is an ongoing search to develop techniques for detection of heavy metals which are highly toxic and can cause damaging effects even at very low concentrations. In this present study, we report a label-free electrochemical method based on the direct voltammetric response of human cervical carcinoma (HeLa) cells on a highly sensitive graphene modified electrode. Five heavy metals were tested with the method and the results were validated by the traditional methyl tetrazolium (MTT) assay. The results revealed that the most toxic metal was Cr, followed by Cd, Cu, Pb and Zn. A good correlation between the two methods was observed. This work will be beneficial in providing a novel monitoring method to detect hazardous pollutants in the field of environmental toxicology.