A novel room temperature nucleic acid detection method based on immobilization of adenosine-based molecular beacon

•A room temperature nucleic acid detection method.•A novel molecular beacon technique based on polyadenosine and coralyne interaction.•The biosensor is capable of discrimination single base mismatched sequences.

We developed a novel room temperature fluorescence DNA biosensor based on immobilization of well designed adenosine-based molecular beacon (ABMB). In the presence of coralyne, a small molecule which can react with adenosines, the ABMB would form a hairpin structure just like traditional molecular beacon used extensively. In our experiments, two kinds of adenosine-based molecular beacon probes with twelve adenosines bases at each end (A12-MB1-A12 and A12-MB2-A12), and their complementary target DNA, non-complementary target DNA and single base mismatched DNAs were used as models to demonstrate the proof-of-concept. Under optimized conditions, the detection limit was estimated to be 50 pM based on S/N = 3. The ability of our developed biosensor for discriminating the single base mismatched DNA related to a human genetic disease, hereditary tyrosinemia type I, was improved undoubtedly once A12-MB2-A12 was used as capture probe comparing with previous report. It is worth to mention that the whole assay procedures were conducted under room temperature.