'Dip Chip' warns of toxicity in real time

Tel Aviv, May 15 (IANS) Now, there's a quick check for synthetic chemicals and poisons that contaminate water or food supplies and generate bodily reactions from minor illness to painful death.

Yosi Shacham-Diamand, professor of engineering at Tel Aviv University, and Shimshon Belkin of the Hebrew University of Jerusalem, have married biology and engineering to design a biosensor called the "Dip Chip," which detects toxicity quickly and accurately.

The Dip Chip contains microbes designed to exhibit a biological reaction to toxic chemicals, duplicating the biological responses of humans or animals. The bio-reaction is converted into an electronic signal that can be read by the user.

When perfected for commercial use, the chip might be esily plugged into a mobile device to determine toxicity, says Shacham-Diamand, the journals Electrochimica Acta and Sensors and Actuators B: Chemical report.

The new chips are based on genetically modified microbes developed in Belkin's lab. When they are exposed to toxic or poisonous substances, they produce a measurable biochemical reaction - and this is where Shacham-Diamand's work begins, according to a Tel Aviv statement.

"The device, which looks like a dip stick, immobilizes these specially-produced microbes next to the sensing electrodes. Once the microbes come into contact with a questionable substance they produce a chemical signal that is converted to an electrical current by an device that can interpret the signals, producing a binary 'toxic' or 'not toxic' diagnosis," adds Shacham-Diamand.