Background: In April 2010 contamination in jet fuel caused the throttles of two engines on a Cathay Pacific flight to stick while in flight and nearly caused the lives of 322 passengers and crew on board. Such incident is just one of the examples of the dangers posed by cross contamination in the fuel. FAME or biodiesel has the property to ‘stick’ to surfaces and small traces of FAME can be found in jet fuel leading to cross contamination. At high concentrations FAME may impact the thermal stability of the jet fuel leading to coke deposits in the fuel system. FAME contamination can also impact the freezing point of jet fuel resulting in fuel gelling. Such conditions may result in engine operability problems and possible engine flameout. Currently the aviation industry allows up to 5 ppm FAME in its jet fuel. Yet because 5 ppm FAME in jet fuel is difficult to detect most sophisticated instrumentations such as GC FT-IR and HPLC do not have the sensitivity for 5 ppm FAME detection. Therefore there is a strong need for a highly sensitive quick easy and direct ppm-level detection of FAME in the aviation industry. Technology Description: Researchers at the University of Tennessee (UT) have developed novel thin film sensors with high sensitivity toward FAME contaminant in diesel or jet fuel. Small strips of these sensors have been tested to detect the trace biodiesel (FAME) contaminant in diesel at as low as 0.5 ppm in less than 30 minutes.