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

Abstract

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 50pM 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.