Affinity-Modulated Molecular Beacons on MoS2 Nanosheets for MicroRNA Detection.
Mingshu XiaoArun Richard ChandrasekaranWei JiFan LiTiantian ManChang-Feng ZhuXizhong ShenHao PeiQian LiLi LiPublished in: ACS applied materials & interfaces (2018)
DNA-functionalized layered two-dimensional transition-metal dichalcogenides have attracted tremendous interest for constructing biosensors in recent years. In this work, we report diblock molecular beacons with poly-cytosine (polyC) tails anchored on molybdenum disulfide (MoS2) nanosheets as probes for microRNA detection. The polyC block is adsorbed on MoS2 and the molecular beacon block is available for hybridization to the target; duplex-specific nuclease provides signal amplification by target recycling. By changing the length of polyC, we regulate the density of probes on MoS2 and inhibit the adsorption of enzyme-cleaved oligonucleotides, thereby leading to higher quenching efficiency. PolyC-mediated molecular beacons on MoS2 have very low background signal, ultrahigh sensitivity (limit of detection ∼3.4 fM), specificity to detect a single nucleotide mismatch, and selectivity to detect target microRNA from serum samples. This detection platform holds great potential for quantitative analysis of miRNAs in clinical diagnosis and biomedical research.
Keyphrases
- transition metal
- quantum dots
- reduced graphene oxide
- single molecule
- label free
- loop mediated isothermal amplification
- highly efficient
- nucleic acid
- room temperature
- real time pcr
- sensitive detection
- small molecule
- living cells
- gold nanoparticles
- mass spectrometry
- climate change
- dna binding
- solid phase extraction
- liquid chromatography
- ion batteries