Compelling medical need: Cancer is the second leading cause of death ~ 292, 540 men and 269,840 women (2009) in theUnited States, second only to heart disease (American Cancer Society, Cancer statistics, 2009). Cancer death rate only dropped slightly over the last three decades, from ~200 to ~ 180 per 100,000 in 1975 and 2005, respectively (US mortality data, Centers for Disease Control and Prevention, 2008), in part because of the fact that cancer is a complex and very heterogenous disease, in part because of the lack of cancer diagnosis technology. Sensing of these biomarkers to construct a comprehensive, quantitative and accurate profile becomes critical for more accurate diagnosis and better disease management.

We develop a novel label-free broadband impedance biosensor (BIMBS) to target early detection of prostate cancer as an example, because according to American Cancer Society, one man in 6 will get prostate cancer during his lifetime, and 1 man in 35 will die of this disease. Prostate-speci?c antigen (PSA) is now the most widely used noninvasive screening tool in solid tumors. However, the inability to determine, at diagnosis, which prostate cancers will progress or already have progressed to disseminated disease is one of the foremost problems in the clinical management of prostate cancer. This relies on detection (multiplexing) of the multiples biomarkers (in addition to PSA), specifically on improving the accuracy in the clinical gray zone (4-10 ng/ml). The proposed concept of the broadband impedance sensing technique can be widely extended for detection of other types of cancers and diseases.