Zhang Saimei, Dong Jiangxue, Zhao Yanping, Wang Congcong, Fan Yajie, Li Yanlei, Su Ming, Li Na, Shen Shigang, Gao Zhongfeng, Xia Fan
Key Laboratory of Analytical Science and Technology of Hebei Province, College of Chemistry and Materials Science, Hebei University, Baoding 071002, P. R. China.
Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China.
Anal Chem. 2025 Sep 9;97(35):19119-19127. doi: 10.1021/acs.analchem.5c02598. Epub 2025 Aug 27.
Finely tunable detection of microRNAs (miRNAs) is crucial for personalized medicine and cancer diagnosis, and it is a challenge to construct a tunable sensor for miRNA detection due to the diversity and complexity of cancer patient samples. This study introduces a three-dimensional (3D) DNA walker mediated by a remote toehold strand displacement reaction, which addresses the challenge of achieving tunable detection limits and sensitivities for microRNA-21 (miR-21) at a kinetic level, enabling specific recognition of cancer cells. By engineering a spacer domain within the DNA walker, the kinetics of the strand displacement reaction can be precisely modulated, thereby controlling the walking efficiency and achieving tunable detection with a detection limit range from 32 aM to 290 pM and a broad dynamic range from ∼1100-fold to ∼283,000-fold. This approach leverages the programmability of DNA molecules to design probe structures tailored to experimental requirements, offering high sensitivity and specificity and a wide detection limit. The 3D DNA walker, driven by Zn, allows for rapid and accurate imaging of miR-21 in cancer cells, thereby effectively differentiating cancerous cells from normal cells. The proposed method not only demonstrates a high degree of specificity in recognizing miR-21 but also provides a robust foundation for clinical diagnosis and holds promise for applications in personalized medicine, early disease detection, and drug development. These findings underscore the potential of this remote toehold-mediated DNA walker as a powerful tool for real-time monitoring and dynamic detection of disease biomarkers, enhancing the precision and efficacy of therapeutic interventions.
对微小RNA（miRNA）进行精细可调的检测对于个性化医疗和癌症诊断至关重要，然而，由于癌症患者样本的多样性和复杂性，构建用于miRNA检测的可调传感器是一项挑战。本研究引入了一种由远程引发链置换反应介导的三维（3D）DNA步行器，该步行器在动力学水平上解决了实现对微小RNA - 21（miR - 21）的可调检测限和灵敏度的挑战，从而能够特异性识别癌细胞。通过在DNA步行器中设计一个间隔域，可以精确调节链置换反应的动力学，进而控制步行效率，并实现检测限范围从32 aM到290 pM、动态范围从约1100倍到约283,000倍的可调检测。这种方法利用了DNA分子的可编程性来设计符合实验要求的探针结构，具有高灵敏度、高特异性以及宽检测限。由锌驱动的3D DNA步行器能够对癌细胞中的miR - 21进行快速准确的成像，从而有效地将癌细胞与正常细胞区分开来。所提出的方法不仅在识别miR - 21方面表现出高度特异性，还为临床诊断提供了坚实基础，并在个性化医疗、疾病早期检测和药物开发中具有应用前景。这些发现强调了这种远程引发介导的DNA步行器作为实时监测和动态检测疾病生物标志物的强大工具的潜力，可提高治疗干预的精准度和疗效。
