KLK3 and Familial prostate cancer: reported a bead-based SERS assay for simultaneous detection of dual PSA makers namely free PSA (f-PSA) and complexed PSA (c-PSA) from prostate cancer patients by using the total PSA (t-PSA) antibody-conjugated magnetic beads as capture substrates and two different types of antibody-conjugated SERS nanotags as detection probe [86].