Bright Idea (IMAGE) Arizona State University Caption The paper describes a new technique for identifying tumor-derived extracellular vesicles (EVs). The method relies on differently shaped nanoparticle probes that refract light at different wavelengths, one spherical (green) and one rod-shaped, (red). One probe identifies a surface protein linked with pancreatic cancer, known as ephA2, and the other identifies a common EV surface protein. Only pancreatic cancer-derived EVs express both proteins and thus bind both nanoparticles to emit a brilliant yellow signal that allows these disease-linked EV's to be easily detected for diagnostic purposes. This method can also usefully track the success of anti-cancer treatment by measuring the abundance of tumor-derived EV's over the course of therapy Credit Graphic by Jason Drees Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.