Quick Tests For Fatal Diseases Possible With New Sensor

Professor Ulrich Krull's new DNA hybridization detection system combines the precision of DNA chemistry with the speed of fibre optics to provide on-the-spot testing for organic molecules. "Most existing equipment needs long periods of time to work, but we can achieve a determination in seconds," says Krull, associate dean of sciences at the University of Toronto at Mississauga.

Biosensors use actual organic molecules to detect reactions and convert them to a signal that humans can read quickly. Krull's experiments involve attaching strands of DNA, the molecular basis of life, directly to a fibre optic surface. The strands bind to a specific DNA or RNA sequence the sensor is set to look for, and the resulting chemical changes are detected via the optical fibre.

One application Krull has tested successfully in the lab involves rapid screening for genetic material associated with fast-moving fungal infections, a leading cause of death in individuals with weakened immune systems. Similar technology could be the foundation for disposable diagnostic devices that would make screening for strep infections, hepatitis or AIDS as easy as current home pregnancy tests, says Krull, who also holds the university's Astra Pharma Chair in Biotechnology.

The hybridization detection system is currently being developed by FONA Technologies of Mississauga.

CONTACT: Bruce Rolston
U of T Public Affairs
(416) 978-6974
e-mail: bruce.rolston@utoronto.ca