Hexagonal boron nitride nanosheet as an effective nanoquencher for the fluorescence detection of microRNA

Two-dimensional (2D) hexagonal boron nitride nanosheet (h-BNNS) is proposed as an effective nanoquencher for fluorescence detection of biocompatible microRNA. Compared with bulk hexagonal boron nitride (h-BN), the exfoliated ultrathin nanosheet has a narrow band gap and increased conductivity, thus enabling fast electron transfer with this electron acceptor for more effective fluorescence detection of microRNA. Remarkably, using the nanoprobe consisting of h-BNNS and FAM dye-labeled ssDNA, a low detection limit of 2.39 nM is achieved and a rapid fluorescence response is observed compared with previously reported fluorescence sensing materials. More importantly, this sensing system could also distinguish base-mismatched microRNA, suggesting that the proposed sensing platform held excellent selectivity and great promise for application in the detection of nucleotide polymorphism. This work will benefit microRNA-related fundamental research and disease diagnosis.

Automated summary

This study introduced the use of two-dimensional hexagonal boron nitride nanosheet as a nanoquencher for fluorescence detection of microRNA, showing narrow band gap and high conductivity. By combining it with FAM dye-labeled ssDNA, a low detection limit and rapid response were achieved, demonstrating excellent selectivity and potential application prospects in nucleotide polymorphism detection.