Ultrasensitive DNA Origami Plasmon Sensor for Accurate Detection in Circulating Tumor DNAs

Early lung cancer screening by computed tomography is hampered by pulmonary nodules caused by massive COVID-19 infections, necessitating an ultrasensitive approach for the early diagnosis of lung cancers at the single-base level from circular tumor DNAs (ctDNAs). This study introduces an approach that merges DNA origami and DNA scissors technologies in a framework of surface plasmon resonance (SPR) biosensors. By combining the precision of DNA origami probes with the inherent single-base resolution of DNA scissors, this method systematically addresses the limitations of conventional SPR techniques, resulting in enhanced detection accuracy. The synergistic interplay between DNA scissors and DNA origami enables the SPR biosensors to achieve unprecedented levels of sensitivity, precision, and practical utility. This efficacy allows the precise identification of mutations, demonstrated here by detection of the T790M mutation in the EGFR gene and the G12C mutation in the KRAS gene of non-small cell lung cancer patients. With this technique, single-base resolution as well as near zeptomolar-level sensitivity is achieved. As a result, this discovery holds significant potential to advance the field of precision diagnostics. By combining DNA origami and DNA scissors with the capabilities of surface plasmon resonance (SPR), the limitations inherent in conventional SPR techniques are transcended, resulting in an unprecedented level of accuracy in gene detection. The coordination of DNA origami probes and DNA scissors technology induces detectable shifts in refractive index, thereby amplifying SPR signals and elevating sensitivity and precision to previously unattained levels. image