A novel hybrid platform of g-C3N4 nanosheets /nucleic-acid-stabilized silver nanoclusters for sensing protein.

The fabrication of nanomaterials-based sensing platform has attracted a great deal of interest due to their unique properties. Here, we report a novel hybrid platform of g-C3N4 nanosheets/DNA-stabilized Ag nanoclusters (CNNS/AgNCs) for sensing application. In this platform, the fluorescent AgNCs was synthesized using a pair of double-functional ssDNA sequence as a template, including the aptamer segment against thrombin and C-rich segment for AgNCs. Next, the interaction between the fluorescent Apt-AgNCs and CNNS was investigated. It is verified that DNA-stabilized AgNCs could absorb on the CNNS surface via the stronger π-π interaction to form the hybrid platform, whose fluorescence is quenched by CNNS through the photoelectron transfer effect (PET). When targets are introduced into the system, target/Apt-AgNCs complex will fall off from the CNNS surface, resulting in the fluorescence recovery. This hybrid platform can achieve the detection of biomolecule with high sensitivity and selectivity. Considering the fluorescence variability of DNA scaffold AgNCs, this hybrid platform is promising to extend to other target and even multi-target detection.