Fig 1: CLFA system using brown, navy, and red PINs as probes. a Scheme of the CLFA system for detection of prostate-specific antigen (PSA) as a single target. b Photograph images of CLFA strips after developing. * marks represented the concentration level with a boundary for the abnormal range of PSA (4.0 ng mL−1). c Quantitative analysis of PSA based on detection results. d Scheme of the CLFA system for multiplex detection of intercellular adhesion molecule 1 (ICAM1), carbohydrate antigen 19–9 (CA19-9), and PSA as multiple targets. e Illustration of three representative organs in which cancer can occur: Stomach (T1), Pancreas (T2), and Prostate (T3). ICAM1, CA19-9, and PSA are representative biomarkers for each cancer, representatively. f Photograph images of CLFA strips after developing. * marks represented the concentration level with a boundary for the abnormal range of each biomarker (391 ng mL−1 for ICAM1, 37 U mL−1 for CA19-9, and 4.0 ng mL−1 for PSA). f Quantitative analysis of ICAM1, CA19-9, and PSA based on detection results. The red zone represented an abnormal range of each biomarker