Molecular Beacon-Based Fluorescent Biosensor for Sensitive Detection of Single Nucleotide Polymorphism

Abstract

A sensitive fluorescent biosensing strategy based on structure-switching of molecular beacon for the detection of single nucleotide polymorphism is proposed in this study. In the absence of target DNA, only low background fluorescence can be detected since the formation of hairpin structure induces close proximity of fluorophore and quencher. On the contrary, the fluorescence intensity increases significantly after introduction of target DNA because structure-switching of molecular beacon results in separation of fluorophore and quencher. The change of fluorescence intensity is linear with concentration of target DNA, and a molecular beacon-based sensing system for fluorescent detection of single nucleotide polymorphism is fabricated. The target DNA can be sensitively detected in a linear dynamic range from 17.58nM-1.125μM with a low detection limit of 8 nM. Moreover, good reproducibility and high specificity are achieved.

Molecular beacon strategies for sensing purpose

“…Among these methods, the fluorescence has attracted the most attention due to its low cost, ultrasensitivity, and rapid response [76]. In this field, an MB-based ''Y''-designed biosensor with powerful SNP detection capacity was reported.…”

“…Two rapid, sensitive, and simple approaches based on a hairpin structure functionalized LFSB and HO-AuNP biosensor were reported for SNP detection. In the first method, the HO was designed with biotin and a thiol group (at the 3′ and 5′ terminals respectively), which were This method had some advantages, including excellent reproducibility, ultra-specificity, and sensitivity [76]. Though these MB based SNP identification approaches can conquer some of the shortage of old methods of SNP recognition, these procedures have not yet been used for sensitive, accurate, low-cost, and rapid SNP detection in clinical settings [78].…”