To summarize, the fabrication of specific phage-based immunosensors for the ultrasensitive detection of f-PSA and t-PSA in human sera is an encouraging example of effectively harnessing the power of molecular evolution and phage display for the creation of smart detection materials that can recognize and monitor the presence of different forms of prostate cancer biomarkers in human blood [16]. This evidence concerns the gene KLK3 and prostate cancer.