Purdue Graduate Students Examine Samples (IMAGE) Purdue University Caption Purdue graduate students Allison Dill and Livia Eberlin use desorption electrospray ionization, or DESI, to examine samples. They are part of a research team led by Graham Cooks, Purdue's Henry Bohn Hass Distinguished Professor of Chemistry, that uncovered a potential prostate cancer marker. Credit Photo courtesy of Graham Cooks 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.