Fluorescence Quenching of Carbon Nitride Nanosheet through Its Interaction with DNA for Versatile Fluorescence Sensing

Abstract

This work investigates the interaction of carbon nitride nanosheet (CNNS), a recently developed two-dimensional nanomaterial, with DNA and its fluorescence quenching mechanism on fluorophore labeled single-stranded DNA probes. The static quenching through the photoinduced electron transfer (PET) from the excited fluorophore to the conductive band of CNNS is identified. Utilizing the affinity change of CNNS to DNA probes upon their recognition to targets and the PET-based fluorescence quenching effect, a universal sensing strategy is proposed for design of several homogeneous fluorescence detection methods with short assay time and high sensitivity. This strategy is versatile and can be combined with different amplification tools for quick fluorescence sensing of DNA and extensive DNA related analytes such as metal cations, small molecules, and proteins. As examples, two simple fluorescence detection methods for DNA and Hg(2+), one facile detection method coupled with Exo III-mediated target recycling for sensitive DNA analysis, and a ratiometric fluorescence protocol for DNA detection are proposed. This work provides an avenue for understanding the interaction between two-dimensional nanomaterials and biomolecules and designing novel sensing strategies for extending the applications of nanomaterials in bioanalysis.

In situ biosensor for detection miRNA in living cells based on carbon nitride nanosheets with catalytic hairpin assembly amplification

“…P1/P2-CNNS (200 μg/ml) was incubated with different concentrations (0, 0.5, 25, 100, 200, 300, 400, or 600 pM) of miR-106a in SPSC buffer for 4.0 h at room temperature, the fluorescence measurements were performed using a RF-5301PC spectrofluorometer. ( Figure S1), [29,31] which indicated that FAM-P1 and FAM-P2 were assembled on CNNS, thus a successful preparation of the nanoprobe was confirmed.…”

“…P1/P2-CNNS was prepared by assembling P1 and P2 onto the CNNS surface through strong π-π interactions (Scheme 1a). [28,29] Table 1.…”

Graphitic carbon nitride nanosheet-based multicolour fluorescent nanoprobe for multiplexed analysis of DNA

“…It has also been reported that g-C 3 N 4 exhibits excellent biocompatibility and nontoxicity [33]. In comparison to the graphene oxide, the g-C 3 N 4 dispersion in water showed a stronger Tyndall effect than that of graphene oxide, indicating its excellent stability [34]. The good dispersity, biocompatibility, and nontoxicity of g-C 3 N 4 were favorable for studying its interaction with biomolecules and its application in the biosensing field.…”

Laser ablation of molecular carbon nitride compounds

“…Recently, Bojdys and coworkers presented a crystalline triazine-based graphitic carbon nitride with very low hydrogen content (0.51 wt%) and a carbon-tonitrogen ratio close to the theoretical one for g-C 3 N 4 [15]. Owing to their optoelectronic properties, these polymers have nonetheless found potential applications, from light-induced catalysis including hydrogen evolution from water [16,17] to chemical sensing [18,19] and electronic devices [15,20]. Advancement in these applications hinges on the detailed characterization of their physical properties, which so far have been limited due to difficulties in material processing.…”