KLK3 and cancer: For example, Xiong et al. reported the magnetic particle integrated microfluidic chip applied in SPR for a simple, rapid, and highly sensitive detection of multi cancer biomarkers (prostate specific antigen (PSA), alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), cancer antigen (CA) 125, and CA19-9) with the detection limit of PSA down to 0.2 pg mL−1 and bacterial species (E. coli O157: H7 and S. aureus) in 1 μL of body fluids within 8 min (Figure 2 and Figure 3) [78].