Graphene quantum dots-NaYF4:Yb,Er hybrid with significant enhancement of upconversion emission for fluorescent detection of carcinoembryonic antigen with exonuclease III-aided target recycling amplification

Graphene quantum dot-NaYF4:Yb,Er was made via hydrothermal synthesis. The resulting hybrid shows good water-solubility, small particle size of 11.5 nm and significant enhancement of upconversion emission. Further, the hybrid was designed as an upconversion biosensing nanoplatform for detection of carcinoembryonic antigen based on the exonuclease III-aided target recycling amplification. Firstly, the linker DNA (LDNA) is covalently attached to...