A semi-automated multiple biomarker-based diagnostic microfluidic device for on-line capture and detection of prostate cancer biomarkers is described herein.  In the United States, the lifetime risk of men developing prostate cancer is 1 in 7.  Strategies in detection and staging of prostate cancer include prostate specific antigen (PSA) test, digital rectal exam (DRE) and biopsy. These practices often fall short in terms of sensitivity, specificity and inability to distinguish between aggressive and indolent forms of prostate cancer.  Inaccurate sensitivity and specificity can lead to unnecessary treatments that adversely affect the patients’ quality of life.  Measurement of small panels of molecular biomarkers in serum holds tremendous potential for cancer diagnostics and personalized therapy. The protein panel includes PSA, CD-14, ERG, GOLM-1, PEDF-1, IGF-1, VEGF-D and IGFBP-3, many of which are thought to be specific for aggressive prostate cancer. The protein analytes are captured from serum samples in a two channel on-line microfluidic chamber by magnetic beads labeled with antibodies and signal transducing elements.  Captured analytes are then magnetically separated, washed, and introduced into a two channel detection chamber housing an array of 8 or 16 nanostructured, antibody-labeled electrodes.  Ultra-low detection limits in the sub fg ml^-1 range was achieved for the protein panel. Using this strategy, 8-16 proteins can be detected simultaneously in 30 minutes.  Measurements of the selected biomarker panel will be tested with prostate cancer patient samples in future to assess its diagnostic capability.