Tao Cheng, Jiaying Sun, Zhenghe Xu, Jiabao Yu, Jin Jiao, Peng Miao
Accurate quantification of low-concentration tumor-derived miRNAs in complex biological samples is critical for cancer clinical diagnosis yet remains challenging due to the lack of convenient and sensitive detection methods. Herein, we report a smart dual-amplification electrochemical analyzer (SDEA) for glioma grading based on product-activated tripedal DNA walker. Target miRNA initiates strand displacement amplification to generate abundant specific DNA strands that release walker strands. The SDEA strategy circumvents nonspecific binding between the potential interferent and the DNA walker. In addition, two-round amplification is involved, including strand displacement amplification and tripedal DNA walking, promising high sensitivity for target miRNA detection. The proposed SDEA allows staging analysis of gliomas in clinical cohorts and highlights the great potential of DNA nanotechnology in disease diagnostics.