A new method based on guanine rich aptamer structural change for carcinoembryonic antigen detection.

Carcinoembryonic antigen (CEA) is one of the most widely used tumor marker around the world, it mainly used for gastrointestinal cancers, especially in colorectal malignancy. At present, the detection methods of CEA are mostly based on antigen-antibody binding, whereas these methods were limited by the high costs and long waiting times in massive population tumor screening. During the experiments, we interestingly found that the fluorescence signal would be dramatically altered when the secondary structure of fluorescent modified guanine-rich DNA changed. Then we explored the reasons and established a new method for CEA detection, this method brings a simple, fast and cheap sensing platform for detection of biomarkers. It has great potential in screening of tumors among the group and is expected to provide prospective effects for tumor treatment.