A fluorescent platform integrated with a “one-pot” nicking endonuclease signal amplification and magnetic separation for simultaneous detection of tumor markers

Although Enzyme-linked immunosorbent assay (ELISA) has been widely used for biomedical research, simultaneous sensitive and cost-effective detection of multiple biomarkers is challenging. Herein, we proposed a "one-pot" nicking endonuclease signal amplification (NESA)-based fluorescent aptasensor for simultaneous detection of carcinoembryonic antigen (CEA) and alpha fetoprotein (AFP). Firstly, two aptamers were synchronously immobilized on the surface of magnetic nanoparticles (MNPs) by coupling with two complementary DNA (cDNA). CEA and AFP specifically recognized the aptamers and then the released cDNA (ssDNA) from the double-strands (dsDNA) triggers NESA, further breaking two detection probes which were labeled with the fluorescent dye (FAM and ROX) and its quencher (BHQ