There have been ongoing efforts to develop more sensitive and fast quantitative screening of cancer markers by use of fluorometric immunochromatographic test strip (ICTS) since the remarkable advances in fluorescent nanomaterials. Semiconducting polymer dots (Pdots) have recently emerged as a new type of biocompatible fluorescent probes with extraordinary brightness which is suitable for biological and clinical use. Here we developed Pdot-based ICTS for quantitative rapid screening of prostate-specific antigen (PSA), alpha-fetoprotein (AFP), and carcinoembryonic antigen (CEA) in 10 min. By taking advantage of the ultrahigh fluorescence brightness of Pdots, this immunosensor enabled much better detection sensitivity (2.05, 3.30, and 4.92 pg/mL for PSA, AFP, and CEA, respectively), which is at least 2 orders of magnitude lower than that of conventional fluorometric ICTS. Furthermore, we performed proof-of-concept experiments for simultaneous determination of multiple tumor markers in a single test strip. These results demonstrated that this Pdot-based ICTS platform is a promising candidate for developing new generations of point-of-care diagnostics. To the best of our knowledge, this is the first example of Pdot-based ICTS with multiplexing capability.
Analytical chemistry. 2017 Dec 29 [Epub ahead of print]
Chia-Chia Fang, Chia-Cheng Chou, Yong-Quan Yang, Wei-Kai Tsai, Yeng-Tseng Wang, Yang-Hsiang Chan