In this work, a label-free fluorescence biosensor was proposed for simple detection of the Kras wild type by using the three way DNA junction-driven catalyzed hairpin assembly strategy. In this system, a three-way DNA junction probe (JP) and two hairpin probes (H1 and H2) were designed. In the presence of the Kras wild type, an autocatalytic DNA machine can be activated. This leads to the generation of numerous free G-rich sequences, which can associate with a fluorescent dye N-methylmesoporphyrin IX (NMM) to yield an amplified fluorescence signal for the target detection. This sensing platfor...
