Label-free capacitive E. coli biochip for determining chemicals that induce cellular toxicity

摘要

A novel method for the detection of toxicity of chemicals on living cells was developed using carboxy-CNT activated gold interdigitated (GID) capacitor arrays immobilized with viable wild-type E. coli (biochip). The toxicity detection is based on label-free non-Faradaic electrochemical impedance spectroscopy (nFEIS). The technique enabled monitoring the stress/toxicity imposed by chemicals on viable bacteria. Here, model stress inducing chemicals such as, acetic acid (metabolic), H2O2 (oxidative) and sodium chloride (salt) were tested with the developed biochip. The resulting response of biochip determined the concentration dependent toxicity levels imposed by chemicals on the cells. Interesting feature of the developed biochip sensor is the characteristic dispersion peaks at 463 and 582 MHz that determined the toxic nature of the chemicals. The biochip developed finds advantages in labeling chemicals that are potentially harmful to humans and the ecosystem.