A novel plasmonic sensor device developed by scientists at the University of Illinois at Urbana-Champaign, enables early detection of biomarkers for many types of cancer and potentially for several other diseases as well. Currently, the diagnostic methods available for detecting cancer and other biomarkers, are capable of detecting only fairly higher concentrations of the substance, which tends to be a limiting factor in early diagnosis. A novel device developed by the current research team permits detection of CEA concentrations as low as 1 nanogram per milliliter.