R. Popovtzer, T. Neufeld, E.Z. Ron, J. Rishpon and Y. Shacham-Diamand
electochemical sensor, bio-chip, whole cell biosensors, lab on a chip
An electrochemical Nano-Bio-Chip for water toxicity detection is presented. Integrating living cells with electronic devices contributes functional information regarding the effect of toxicants on living organisms. Bacteria, which have been genetically engineered to respond to environmental stress, act as a sensor element and trigger a sequence of processes, which leads to generation of electrical current. <br>The device is composed of two units: a disposable silicon chip containing an array of nano-volume electrochemical cells that housing the biological material, and a reusable unit that includes a multiplexer and a potentiostat connects to a pocket PC for sensing and data analysis. Each of the electrochemical cells in the array can be monitored simultaneously and independently. <br>This novel, portable and miniature device provides rapid and sensitive real-time electrochemical detection of acute toxicity in water. A measurable current signal, well above the noise level, was produced within less than 10 minutes of exposure to various concentrations of toxicants. The results show a direct correlation between the toxicant concentration and the induced current. This work demonstrates the main advantages of the nano-bio-chip, including miniaturization, portability, high throughput, high signal to noise ratio, requirement for small samples, and production of on-site and real-time results.